Reference:Movements: Difference between revisions

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<div class="rp-era"><div class="rp-era-name">Oyster / Oysterdate Precision</div><div class="rp-chips">[[#cal-1210|1210]] [[#cal-1215|1215]] [[#cal-1216|1216]] [[#cal-1220|1220]] [[#cal-1225|1225]] [[#cal-1200|1200]]</div></div>

<div class="rp-era"><div class="rp-era-name">Vintage sport (1950s–80s)</div><div class="rp-chips">[[#cal-1030|1030]] [[#cal-1035|1035]] [[#cal-1036|1036]] [[#cal-1065|1065]] [[#cal-1066|1066]] [[#cal-1530|1530]] [[#cal-1520|1520]] [[#cal-1535|1535]] [[#cal-1525|1525]] [[#cal-1560|1560]] [[#cal-1565|1565]] [[#cal-1570|1570]] [[#cal-1575|1575]]</div></div>

<div class="rp-era"><div class="rp-era-name">Modern sport (1988–2023 coverage)</div><div class="rp-chips">[[#cal-3000|3000]] [[#cal-3035|3035]] [[#cal-3075|3075]] [[#cal-3085|3085]] [[#cal-3130|3130]] [[#cal-3132|3132]] [[#cal-3135|3135]] [[#cal-3175|3175]] [[#cal-3185|3185]] [[#cal-3186|3186]] [[#cal-3187|3187]]</div></div>

<div class="rp-era"><div class="rp-era-name">Modern sport (1988–2023 coverage)</div><div class="rp-chips">[[#cal-3000|3000]] [[#cal-3035|3035]] [[#cal-3075|3075]] [[#cal-3085|3085]] [[#cal-3130|3130]] [[#cal-3132|3132]] [[#cal-3135|3135]] [[#cal-3175|3175]] [[#cal-3185|3185]] [[#cal-3186|3186]] [[#cal-3187|3187]] [[#cal-3230|3230]] [[#cal-3235|3235]] [[#cal-3285|3285]]</div></div>

<div class="rp-era"><div class="rp-era-name">Milgauss</div><div class="rp-chips">[[#cal-1580|1580]] [[#cal-3131|3131]]</div></div>

<div class="rp-era"><div class="rp-era-name">Milgauss</div><div class="rp-chips">[[#cal-1080|1080]] [[#cal-1580|1580]] [[#cal-3131|3131]]</div></div>

<div class="rp-era"><div class="rp-era-name">Early chronograph</div><div class="rp-chips">[[#cal-13|13]]</div></div>

<div class="rp-era"><div class="rp-era-name">Daytona chronograph</div><div class="rp-chips">[[#cal-72|72]] [[#cal-72a|72A]] [[#cal-72b|72B]] [[#cal-722|722]] [[#cal-722-1|722-1]] [[#cal-727|727]] [[#cal-4030|4030]] [[#cal-4130|4130]]</div></div>

<div class="rp-era"><div class="rp-era-name">Daytona chronograph</div><div class="rp-chips">[[#cal-72|72]] [[#cal-72a|72A]] [[#cal-72b|72B]] [[#cal-722|722]] [[#cal-722-1|722-1]] [[#cal-727|727]] [[#cal-4030|4030]] [[#cal-4130|4130]] [[#cal-4131|4131]] [[#cal-4132|4132]]</div></div>

<div class="rp-era"><div class="rp-era-name">Oysterquartz</div><div class="rp-chips">[[#cal-5035|5035]] [[#cal-5055|5055]]</div></div>

</div>

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== Early chronograph movement

The early Oyster chronograph references use Valjoux ébauches, with Rolex caliber designations that should be kept distinct from the maker’s base number. Available auction records support a limited Cal. 13 / Valjoux 23-family entry~~; they do~~ not ~~establish that~~ every early Rolex chronograph ~~used~~ the ~~same execution~~.

The early Oyster chronograph references use Valjoux ébauches, with Rolex caliber designations that should be kept distinct from the maker’s base number. Available auction records support a limited Cal. 13 / Valjoux 23-family entry. That evidence concerns the 3525 and does not identify every early Rolex chronograph movement.

Ref. [[Reference:2021|2021]] is a pre-Oyster monopusher. Published descriptions give movement sizes from 13 to 16½ lignes; Uhrenkosmos names a Valjoux VZ in one early monopusher, while auction catalogues describe different executions. The available records do not support a reference-wide caliber assignment. Keep these descriptions separate from the Cal. 13 entry below. [[https://www.uhrenkosmos.com/rolex-daytona-seine-technik-und-geschichte/ Uhrenkosmos, early monopusher movement]] [[https://www.phillips.com/detail/rolex/115419 Phillips, case 12'010]] [[https://www.cambiaste.com/it/asta-0795/rolex---rarissimo-cronografo-due-contatori-da-polso-monopulsante-in-ac-270066 Cambi, steel case 14xxx]]

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Prince grades run Prima → Extra Prima → Ultra Prima, with higher jewel counts, more adjustment positions, and stricter chronometer testing. Only Extra Prima and Ultra Prima watches carry "Chronometer" or "Observatory" dial marks. Rolex submitted Prince movements to the National Physical Laboratory at Kew for rate certificates independent of the Swiss Bureaux Officiels Suisse de Contrôle. Its often-cited 1914 Class A Kew certificate belongs to an earlier ladies' wristwatch movement, while Prince testing at Kew-Teddington began in 1928.

The Prince Imperial pocket watch, ref. [[Reference:1645|1645]], is also catalogued with shaped manual movements. Sotheby’s records a 17-jewel Class A Observatory movement, number 1,000,823. Antiquorum describes other 1645 examples as 17-jewel Ultra Prima or Observatory movements, measured at 14½, 16½ and 17 lignes. These are separate watches; the catalogues do not establish a numbered caliber sequence.

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The architecture of Cal. 360 is disputed. Christie's describes a 1938 ref. 2835 "Prince Elegant" with a tonneau-shaped 15-jewel movement, and Charles Jarman's ''The Rolex Reference Guide'' (4th edition) calls Cal. 360 a manual, small-seconds, tonneau-shaped movement with a SuperBalance. Watch Doctor’s online chart instead lists a rectangular, 18-jewel movement measuring 18 × 27mm. The page does not identify an underlying Rolex document.

Jarman dates Cal. 360 to 1937. The expansion of the HW designation remains unconfirmed; it should be retained as a designation rather than expanded to Hans Wilsdorf. The differing shape and jewel descriptions need comparison with the movement in the individual watch.

Jarman dates Cal. 360 to 1937. The expansion of the HW designation remains unconfirmed; it should be retained as a designation rather than expanded to Hans Wilsdorf. The differing shape and jewel descriptions need comparison with the movement in the individual watch. Ineichen’s 2016 catalogue attributes C.360 to a Prince ref. 1880 and describes a nickel-plated lever movement. That is one lot-level attribution; it does not resolve the conflicting descriptions above. [https://ineichen.com/upload/iblock/83c/fnnltq7byndm2n2lwa14zfgz3qzl1tuc.pdf Ineichen, Auction 164, lot 133]

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== Early manual-wind Oyster examples ==

The early cushion-case Oyster references used manual movements, but the available catalogue descriptions do not support one movement assignment for every reference. For [[Reference:1069|ref. 1069]], Antiquorum describes a 15-jewel 11-ligne manual movement on its 2003 example; Christie's describes an unnamed 15-jewel lever movement, and a dealer-photographed example shows a 17-jewel Rolex movement. Keep each description with its watch. Aste Bolaffi's Marconi Oyster has a 15-jewel FHF 30-based movement and the number 1069 on its case, but the catalogue does not identify that number as the reference. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-41-480 Antiquorum 2003]; [https://www.christies.com/lot/lot-3892839 Christie's]; [https://www.1stdibs.com/jewelry/watches/wrist-watches/rolex-nickel-silver-cushion-shaped-oyster-original-dial/id-j_18189072/ dealer photo set]; [https://www.astebolaffi.it/en/lot/268/87/detail Aste Bolaffi 2022]

For [[Reference:1072|ref. 1072]], Antiquorum describes 10-ligne, 18-jewel movements in two examples. Bonhams calls a separate example a 15-jewel Prima. Cool Auction labels the movement Cal. 10½ and reports 15 jewels, 18,000 beats per hour and a maximum 38-hour reserve on a Bucherer-signed watch. The same dealer attributes a Superbalance and Breguet hairspring to that movement. Hess Fine Auctions reports a manual 15-jewel movement in its 2023 lot. Watch Collecting describes another example as manual-wind but gives no caliber or jewel count. Toovey’s title calls its circa-1938 example Ultra Prima but gives no movement specification. The Cool Auction caliber label has no corroboration in the other records; the lots do not establish a single movement assignment or grade across the reference. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-96-82 Antiquorum, Hong Kong, 1997]; [https://www.collectorsquare.com/en/watches/rolex/prima/lpi Antiquorum and Bonhams archive]; [https://www.cool-auction.net/gallery/23866/ Cool Auction]; [https://www.hessfineauctions.com/auction-lot/superior-rolex-oyster-1072-large-cushion-vintage_98542e8bd8 Hess Fine Auctions, lot 3211]; [https://collecting.com/for-sale/1938-rolex-oyster-2 Watch Collecting]; [https://www.tooveys.com/lots/613066/a-rolex-oyster-ultra-prima-chrome-cushion-cased-gentlemans-wristwatch Toovey’s]

For [[Reference:1073|ref. 1073]], Antiquorum names a 10½-ligne Extra Prima movement with 15 jewels. Christie’s calls its 15-jewel movement Prima; Bonhams calls another example Ultra Prima. These lot descriptions do not establish a shared caliber number or grade across the reference. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-15-258 Antiquorum]; [https://www.christies.com/lot/lot-811717 Christie’s]; [https://www.collectorsquare.com/en/watches/rolex/oyster/ref-rolex-1073/lpi Bonhams archive]

== Bubbleback and early automatic ==

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The Field Manual also lists Cal. 630 against the 3372 suffix variants. Antiquorum explicitly names Cal. 630 in a 3372 with centre seconds ([New York lot 436](https://catalog.antiquorum.swiss/en/lots/rolex-lot-23-436)). The same manual lists subsidiary seconds for one 3372/3 entry, while Christie's catalogue describes a 3372 with small seconds and a 9¾-ligne, 17-jewel movement but gives no caliber number ([case 474309](https://www.christies.com/lot/rolex-oyster-perpetual-chronometre-bubble-back-ref-5091692/?intObjectID=5091692&lid=1)). Keep those statements tied to their sources; they do not establish a Cal. 630 small-seconds variant.

Henrik Korpela identifies Cal. 630 NA in one gold watch catalogued as ref. [[Reference:6074|6074]]; its movement number is 56567. Korpela's photographs show 6030 and 6031 scratched out on the caseback before 6074 was stamped over them ([https://watchesbysjx.com/2015/05/explained-restoring-a-1950s-rolex-oyster-perpetual-ref-6074.html SJX restoration]). Antiquorum's 1992 platinum 6074 lot gives a 9¾-ligne, 17-jewel movement with antishock but names no caliber ([https://catalog.antiquorum.swiss/en/lots/rolex-lot-146-67 lot 67]). Keep each description attached to its watch; the records do not establish a reference-wide caliber assignment.

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Cal. 635 belongs to the early automatic family related to Cal. 620. General movement references describe a subsidiary-seconds layout, 17 jewels and a larger movement than the 9¾-ligne measurements in two 3130 auction entries. Antiquorum catalogued 3130 cases 54932 and 474617 with Cal. 635, 19 jewels, 9¾ lignes and subsidiary seconds ([lot 256](https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-256); [lot 169](https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-169)). Christie's identified case 443093 as Cal. 635 with 19 jewels but centre seconds ([2007 lot 2858](https://www.christies.com/en/lot/lot-5008631)). The latter catalogue description conflicts with the usual seconds layout. Without a visible caliber stamp, keep the centre-seconds attribution attached to that lot; do not treat it as a confirmed Cal. 635 variant.

Ref. [[Reference:1925|1925]] lots name Prima or Ultra Prima grades. Antiquorum describes a 9′′′, 15-jewel Prima; Christie’s names Prima on its 1928 example and Ultra Prima on a 1930s octagonal watch; Sterling Vault records a 15-jewel Ultra Prima. The auction record supplies grade names rather than a numeric caliber assignment. Antiquorum also describes a 1948 ref. [[Reference:2081|2081]] with a 10-ligne, 15-jewel Prima; that lot does not name a caliber. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-203-675 Antiquorum, lot 675]

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| jewels

| ~~17–18~~

| 15–18

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| frequency

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This Aegler-supplied 10½-ligne hand-wound family uses the 700/710 architecture. It has a straight-line lever escapement, monometallic Superbalance adjusted to six positions, self-compensating Breguet balance spring, and swan-neck micrometer regulator, with no documented shock protection. The movement powers the original Air-King 4925 and its Air-Lion, Air-Tiger, and Air-Giant siblings, including the sub-seconds 4365, mid-size 4444, and 4647 Hunter Precision. Its architecture links the pre-war Prince and Bubbleback movements with the post-war automatic Cal. 1030. Cal. 700 and 710 are hand-wound movements; Cal. 720 belongs to the automatic branch. White’s *The Vintage Rolex Field Manual* maps [[Reference:5031|ref. 5031]] to Cal. 710 in a reference table, but auction catalogues describe 5031 examples as automatic date watches. Christie’s [https://www.christies.com/en/lot/lot-204100 listing] records movement number 37519 but no caliber; Antiquorum’s [https://catalog.antiquorum.swiss/en/lots/rolex-lot-120-203 1995], [https://catalog.antiquorum.swiss/en/lots/rolex-lot-53-191 1999] and [https://catalog.antiquorum.swiss/en/lots/rolex-lot-222-285 2009] entries do not name a caliber and report differing sizes and jewel counts. Sotheby’s 2020 and 2022 entries say only “automatic.” The available records do not resolve the conflict, so the 5031 is not assigned to Cal. 710, A.295, 740, or 745 here.

This Aegler-supplied 10½-ligne hand-wound family uses the 700/710 architecture. It has a straight-line lever escapement, monometallic Superbalance adjusted to six positions, self-compensating Breguet balance spring, and swan-neck micrometer regulator, with no documented shock protection. Antiquorum names Cal. 700 in its catalogue for ref. [[Reference:3358|3358]], case 51,419, with 18 jewels; its ref. [[Reference:2081|2081]] case 599,744 lot names the same caliber and grade but records 15 jewels. The discrepancy is unresolved, so the jewel count is left unspecified here. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-225 Antiquorum, ref. 3358] [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-226 Antiquorum, ref. 2081] The movement powers the original Air-King 4925 and its Air-Lion, Air-Tiger, and Air-Giant siblings, including the sub-seconds 4365, mid-size 4444, and 4647 Hunter Precision. Its architecture links the pre-war Prince and Bubbleback movements with the post-war automatic Cal. 1030. Cal. 700 and 710 are hand-wound movements; Cal. 720 belongs to the automatic branch. White’s *The Vintage Rolex Field Manual* maps [[Reference:5031|ref. 5031]] to Cal. 710 in a reference table, but auction catalogues describe 5031 examples as automatic date watches. Christie’s [https://www.christies.com/en/lot/lot-204100 listing] records movement number 37519 but no caliber; Antiquorum’s [https://catalog.antiquorum.swiss/en/lots/rolex-lot-120-203 1995], [https://catalog.antiquorum.swiss/en/lots/rolex-lot-53-191 1999] and [https://catalog.antiquorum.swiss/en/lots/rolex-lot-222-285 2009] entries do not name a caliber and report differing sizes and jewel counts. Sotheby’s 2020 and 2022 entries say only “automatic.” The available records do not resolve the conflict, so the 5031 is not assigned to Cal. 710, A.295, 740, or 745 here.

White’s reference table also maps [[Reference:6031|ref. 6031]] to Cal. 710, but the auction records describe automatic date watches. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-17-555 Antiquorum’s 2001 lot] and [https://catalog.antiquorum.swiss/en/lots/rolex-lot-25-143 2002 lot] list 10½ lignes and 19 jewels without naming a caliber; the latter combines refs. 6031 and 6074. [https://www.phillips.com/detail/rolex/160689 Phillips] records movement G3569, and [https://www.sothebys.com/en/buy/auction/2025/fine-watches-pf2570/oyster-perpetual-reference-6031-montre-bracelet-en?locale=en Sotheby’s] G9307, but neither names a caliber. The assignment remains unresolved.

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Antiquorum gives 26 jewels for its Cal. 740 example. That count should be kept with the source's description. A different count in a reference table may reflect a counting convention or a different execution; the number alone does not settle which.

Antiquorum also assigns Cal. 740 to manual-wind [[Reference:6094|ref. 6094]], usually with 17 jewels. Its 2008 lot labels the case 6094/6294; the 2010 and 2012 lots identify ref. 6094 alone. The 2018 listing for case 882812 calls the watch self-winding in its headline while the specification field gives Cal. 740. Keep these as lot-level attributions: the records do not establish that the 6094 Cal. 740 is the automatic 26-jewel movement documented here for ref. 4467. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-203-530 Antiquorum, lot 530]; [https://catalog.antiquorum.swiss/en/lots/rolex-lot-242-134 Antiquorum, lot 134]; [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-tropical-lot-262-291 Antiquorum, lot 291]; [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-oysterdate-precision-lot-313-138 Antiquorum, lot 138].

Surviving examples can have replacement movements or parts. A reference launch date should not be assigned automatically to the movement now inside a particular case.

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Cal. 1215 uses a gradual date change rather than a direct quickset. The date begins moving before midnight and seats as the mechanism completes its cycle.

Christie's places the ref. 6494 changeover between a circa-1956 example with Cal. 1210 and a circa-1958 example with 1215. Other documented fitments include the Speedking 6430, early 6694 production, and refs. 9996/9919. ~~Refs. 6094 and 6294 used Cal. 740 and 790 respectively, rather than 1215.~~

Christie's places the ref. 6494 changeover between a circa-1956 example with Cal. 1210 and a circa-1958 example with 1215. Other documented fitments include the Speedking 6430, early 6694 production, and refs. 9996/9919.

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Cal. 1030 is a bidirectionally wound automatic used in 1950s Oyster references. Its 5.85mm profile ended the domed Bubbleback caseback, while the cutaway "butterfly" rotor stamped ROLEX PERPETUAL PATENTED is the usual visual identifier. Finishing includes perlage on the rhodium-plated main plate, brushed bridges, polished screw heads and red anodized-aluminium reversing wheels. A conventional index regulates the movement; the visible regulator arm distinguishes it from the later free-sprung 1560 and 1570. Documented fitments include ref. 6098 from 1952, Submariners 6536, 6536-1 and 6538, Explorer 6610 and Air-King 6552. The same movement appeared in chronometer and non-chronometer watches.

Cal. 1030 is a bidirectionally wound automatic used in 1950s Oyster references. Its 5.85mm profile ended the domed Bubbleback caseback, while the cutaway "butterfly" rotor stamped ROLEX PERPETUAL PATENTED is the usual visual identifier. Finishing includes perlage on the rhodium-plated main plate, brushed bridges, polished screw heads and red anodized-aluminium reversing wheels. A conventional index regulates the movement; the visible regulator arm distinguishes it from the later free-sprung 1560 and 1570. Documented fitments include ref. 6098 from 1952 and Oyster Perpetual 6567 from the 1950s, Submariners 6536, 6536-1 and 6538, Explorer 6610 and Air-King 6552. The same movement appeared in chronometer and non-chronometer watches.

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Cal. 1530 ran from 1957 to 1965. Its 17-, 25- and 26-jewel versions are concurrent market variants, not a chronological progression. Seventeen-jewel movements appear in a 1958-era ref. 5508, a 5500 ~~and a 1011 Eaton~~, and Rolex’s Technical and Service Information, third edition, discusses the 1520 and 1530 families in its servicing instructions.

Cal. 1530 ran from 1957 to 1965. Its 17-, 25- and 26-jewel versions are concurrent market variants, not a chronological progression. Seventeen-jewel movements appear in a 1958-era ref. 5508 and a 5500, and Rolex’s Technical and Service Information, third edition, discusses the 1520 and 1530 families in its servicing instructions.

Cal. 1530 is the base for the 1520, 1560, 1570 and 1580. They share plates and many service parts, including interchangeable automatic-device bridges, so the engraved bridge number may not identify the movement beneath it. Balance-bridge and regulator form are more reliable.

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The rotor changed from butterfly to half-moon during production. Later movements also gained blued automatic-bridge screws and coloured reversing wheels in place of brass-coloured gears. Rolex describes the red wheel finish as a hardening treatment for aluminium introduced in 1957; collector descriptions often call the wheels purple and Teflon-coated. Rotor and reversing-wheel form help date an example.

The 1530 first entered the Submariner in ref. 5508, followed by 5510; neither was chronometer-rated at launch. It replaced the 10-series in non-chronometer watches, including Precision models, the Air-King, ref. 5504 "Super-Precision" Explorer and the Canadian Explorer-Date with Cal. 1535. Certified models such as the 6542 GMT, 6610 Explorer, Datejust and Day-Date retained 10xx calibers for longer. Strongly documented fitments include refs. 5508, 5510, 5512, 5513, 5500 and 5504. Single-lot support exists for 5501, 5502, 5506, 5516 ~~and 5590/1011 Eaton~~. Bonhams listings for refs. 1002 and 1003 are internally inconsistent and remain unconfirmed. Bonhams lot 84 lists caliber 1530 in ref. 1003 case 573,835 and notes a chronometer certificate dated 22 December 1960. The catalogue is the evidence for this individual attribution; it does not resolve why common reference tables omit the 1530 for 1003.

The 1530 first entered the Submariner in ref. 5508, followed by 5510; neither was chronometer-rated at launch. It replaced the 10-series in non-chronometer watches, including Precision models, the Air-King, ref. 5504 "Super-Precision" Explorer and the Canadian Explorer-Date with Cal. 1535. Certified models such as the 6542 GMT, 6610 Explorer, Datejust and Day-Date retained 10xx calibers for longer. Strongly documented fitments include refs. 5508, 5510, 5512, 5513, 5500 and 5504. Single-lot support exists for 5501, 5502, 5506 and 5516. Bonhams listings for refs. 1002 and 1003 are internally inconsistent and remain unconfirmed. Bonhams lot 84 lists caliber 1530 in ref. 1003 case 573,835 and notes a chronometer certificate dated 22 December 1960. The catalogue is the evidence for this individual attribution; it does not resolve why common reference tables omit the 1530 for 1003.

Rolex specifies a 0.122–0.125mm mainspring for the 18,000-vph 1530 and 1560, against up to 0.125 or 0.128mm for the higher-beat 1520 and 1570. Early unjewelled barrel-bridge arbor holes can wear; Rolex prescribed closing the hole or reaming it for a jewel, while later production received a bushing. Rotor-axle wear is another known fault. On the 1560, a hard shock could push the hairspring into the regulator. Rolex supplied a safety pin free of charge and later made it standard, so both guarded and unguarded examples are correct.

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Auction catalogues often label the date-equipped Cal. 1525 as Cal. 1520. Antiquorum does so on a 1972 ref. 5700, while describing the expected flat hairspring and index-regulated architecture. The chronometer-grade 1560 and 1570 use a Breguet overcoil and Microstella. The Cal. 1525 uses the index regulation associated with the uncertified 5700.

Jewel counts of 17, 25 and 26 reflect parallel market executions. Rolex balance-assembly numbers confirm a flat hairspring for the 1520 and 1525, against a Breguet spring on the 1530 and Microstella on the 1560. The 1525 remains index-regulated.

Jewel counts of 17, 25 and 26 reflect parallel market executions. Rolex balance-assembly numbers confirm a flat hairspring for the 1520 and 1525, against a Breguet spring on the 1530 and Microstella on the 1560. The 1525 remains index-regulated. Waddington’s identifies Cal. 1520, 26 jewels, in a circa-1965 Eaton’s ¼ Century Club watch catalogued as ref. 1011, case 1,301,143. See [[Reference:1011|ref. 1011]].

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Cal. 1560 arrived in 1959 as the chronometer-grade 15xx movement, with a free-sprung balance adjusted to temperature and five positions. Auction catalogues give both 25 and 26 jewels without establishing a pattern. Antiquorum usually describes a Breguet overcoil; its flat-hairspring description for one ref. 1502/1503 is an outlier.

Cal. 1560 arrived in 1959 as the chronometer-grade 15xx movement, with a free-sprung balance adjusted to temperature and five positions. Auction catalogues give both 25 and 26 jewels without establishing a pattern. Antiquorum usually describes a Breguet overcoil; its flat-hairspring description for one ref. 1502/1503 is an outlier. The Oyster Perpetual ref. 1022 is documented with Cal. 1560 by Bonhams, Pandolfini, Adams, and HODINKEE; Tajan describes an automatic movement but names no caliber. Auction catalogues also identify Cal. 1560 in ref. 1024 examples dated circa 1965/66 and circa 1970. Antiquorum lists Cal. 1560 in a ref. 1011 dated 1960, case 546423, and in two lots jointly catalogued as refs. 1010/1011, dated 1960 and 1962. Heritage also lists Cal. 1560 in an undated ref. 1011 sold in 2012. Heritage and Bonhams list Cal. 1560 in individual ref. 1010 lots dated circa 1962 and circa 1967; Antiquorum lists Cal. 1570 in an individual ref. 1010 circa 1968. The Field Manual lists Cal. 1560 for ref. 1010. These records document both attributions; the changeover year remains open. See [[Reference:1010|ref. 1010]].

Cal. 1560 uses free-sprung Microstella regulation; Cal. 1530 uses an index. Watches made from 1959 to 1965 were tested by the Bureaux Officiels de Contrôle de la Marche des Montres, usually under collective certificates and to a standard around −1/+10 seconds per day in five positions. COSC did not exist until September 1973, so describing an early 1560 as COSC-certified is anachronistic.

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Cal. 1570 is the 19,800-vph revision of the 1560, introduced in 1965. One Artcurial ref. 1005 lot is catalogued with Cal. 1550, despite a chronometer-dial description; other 1005 catalogues list 1560 or 1570. This single lot does not establish a 1005 movement variant or resolve whether the movement is original. It retains the free-sprung Breguet overcoil and Microstella regulation, with adjustment to temperature and five positions. Family-wide bridge engraving causes date movements such as the 1575 in a ref. 1665 to appear marked 1570; the engraving alone does not identify the exact caliber.

Cal. 1570 is the 19,800-vph revision of the 1560, introduced in 1965. Christie’s identifies Cal. 1570 in ref. 1011 case 692498, dated circa 1962; its lot chronology overlaps the ref. 1011 Cal. 1560 examples and does not establish a changeover. See [[Reference:1011|ref. 1011]]. One Artcurial ref. 1005 lot is catalogued with Cal. 1550, despite a chronometer-dial description; other 1005 catalogues list 1560 or 1570. This single lot does not establish a 1005 movement variant or resolve whether the movement is original. It retains the free-sprung Breguet overcoil and Microstella regulation, with adjustment to temperature and five positions. Family-wide bridge engraving causes date movements such as the 1575 in a ref. 1665 to appear marked 1570; the engraving alone does not identify the exact caliber. Phillips identifies Cal. 1570 in a circa-1985 ref. 1024, while Dorotheum lists it on a circa-1965/70 example; the auction dates overlap the Cal. 1560 records.

The balance has four Microstella screws in two opposing pairs, not two. Rolex required equal adjustment within each pair to preserve poise. The larger pair changes rate by about two seconds per day and the smaller by about one. On this family the screws sit in the balance rim; the later 3135 platform moves its Microstella nuts to the inner rim.

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== Milgauss ==

~~Rolex introduced~~ the ~~documented Milgauss calibers about fifty years apart~~. ~~Rolex adapted its contemporary sport movements for the Milgauss:~~ Cal. 1580 derives from the 1530 platform~~, and~~ Cal. 3131 from Cal. 3130.

Auction catalogues assign Cal. 1080 to early Milgauss examples, though a later catalogue labels the same 6541 movement number Cal. 1055. Cal. 1580 derives from the 1530 platform; Cal. 3131 derives from Cal. 3130.

=== Cal. 1080 ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

! value

|-

| type

| Automatic

|-

| jewels

| 25 listed for Christie’s case 145'111 and Sotheby’s case 412'479

|-

| documented fitment

| Milgauss 6543 and 6541 examples; one 6541 movement number carries conflicting 1080 / 1055 catalogue labels

|-

| base relationship

| Revolution describes it as modified from Cal. 1030

|}

Christie’s lists Cal. 1080 in 6543 case 145'111. Revolution also assigns the caliber to the 6543 and describes a Cal. 1030 relationship. Sotheby’s called movement N726507 in 6541 case 412'479 Cal. 1080 in 2018; Phillips listed the same case and movement number as Cal. 1055 in 2026. The surviving catalogues document these watch-level labels, not a settled specification or changeover sequence.

Line 2,320:

Line 2,361:

Parachrom was fitted from launch, but the blue version is variously dated between about 2005 and 2007 without a supporting Rolex document. Later examples were rated to Rolex's −2/+2 seconds-per-day standard after its introduction in 2015. Cal. 4130 continued through the ref. 116500LN until Cal. 4131 replaced it in March 2023.

~~<span id="day-date-family"></span>~~

~~== Day-Date ==~~

~~Day-Date calibers form their own family. Four-digit references set both calendar displays through the hands; five-digit references introduced quickset.~~

=== Cal. 3230 ===

=== Cal. ~~1055~~ ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

Line 2,333:

Line 2,369:

|-

| type

| Automatic

| Automatic, no date

|-

| jewels

| frequency

| 25

| 28,800 vph (4 Hz)

|-

| frequency

| power reserve

| 18,000 vph (2.5 Hz)

| Approximately 70 hours

|-

| power reserve

| escapement

| 42h

| Chronergy

|-

| escapement

| hairspring / shock

| Straight-line lever

| Blue Parachrom / Paraflex

|-

| balance

| documented fitment here

| Monometallic

| 124060, 124270, 126000, 126900; catalogue conflicts for some 114300 lots are recorded above

|-

|}

| shock

| KIF

Rolex introduced Cal. 3230 in 2020 as the no-date member of its newer movement generation. Rolex describes the movement with a Chronergy escapement, blue Parachrom hairspring, Paraflex shock absorbers and approximately 70 hours of reserve. The individual reference page remains the authority for a specific watch; catalogue attributions that conflict with Rolex product documentation are recorded as conflicts rather than silently normalized. [https://newsroom-content.rolex.com/-/media/project/rolex/newsroom/rolex/rolex-newsroom-int/about-rolex/history-of-rolex/02_rolex_history_english_2021.pdf Rolex, History of Rolex, 2021]

|}

Cal. 1055 is documented in the first four-digit Day-Date references, from 1956 to 1959: refs. 6510, 6511, 6611, 6612 and 6613. Its rhodium-plated bridges carry oeil-de-perdrix ("partridge-eye") circular graining rather than Côtes de Genève. Documented examples were adjusted to temperature and five positions.

=== Cal. 3235 ===

{| class="wikitable" style="width:280px; font-size:90%;"

Reference histories commonly date the 6611 to 1957 and associate it with the second, chronometer-certified 1055 generation. Phillips lists caliber 1055 on its 1956 gold 6611 and 1055B on its 1958 white-gold 6611B; catalogues do not use the suffix consistently. The dial wording changes to “Superlative Chronometer Officially Certified.”

! detail

! value

6612 catalogues such as [https://www.phillips.com/detail/rolex/CH080115/43 Phillips lot 43], [https://www.bonhams.com/auction/20747/lot/353/ Bonhams lot 353], and [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend lot 67] show the same naming problem: Phillips (1958 platinum case 403,680), Bonhams (circa-1959 gold 6612/8), and Monaco Legend (1958 6612B examples) list Cal. 1055, while [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie’s Dubai lot 65] uses B1055 and other catalogues use 1055B. Keep the calibre label attached to the specific watch and source; those descriptions do not establish that every 6612 retained its original movement.

|-

| type

For examples catalogued as 6612B, Monaco Legend lists Cal. 1055 on yellow-gold case 384,933, white-gold case 394,866 and platinum case 403,679. Phillips lists B1055 on platinum case 446,052; Christie's Dubai uses B1055 while listing the case as 446,062. Treat these as lot-specific catalogue labels. The Dubai case number conflicts with Phillips and Sotheby's, which both give 446,052. [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-182 Monaco Legend, lot 182]; [https://www.monacolegendauctions.com/index.php/auction/exclusive-timepieces-36/lot-26 Monaco Legend, lot 26]; [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend, lot 67]; [https://www.phillips.com/detail/rolex/151223 Phillips, lot 155]; [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie's Dubai, lot 65].

| Automatic, date

|-

The arrival of the free-sprung Microstella balance is disputed. The usual account places it with the 66xx revision, but an auction description identifies a first-generation 6511 as free-sprung. Neither generation has quickset or hacking.

| frequency

| 28,800 vph (4 Hz)

Steel school-watch records create a separate problem: Antiquorum lists 1556 for a 2002 lot and 1066 for a 2013 lot, while Phillips describes later steel Day-Date prototypes with 1555-series movements. These are catalogue descriptions of disputed school/prototype watches, not confirmed 6611 production fitments. See [[Reference:6611|the 6611 record]] for the lot-level distinctions.

|-

| power reserve

Auction catalogues also disagree on the movement fitted to ref. 6511. Phillips lists Cal. 1555 for case 111,654; Phillips lot 41, Antiquorum lot 81, Bonhams lot 156, and Monaco Legend lots 22 and 220 list Cal. 1055. The lot descriptions do not establish whether the 1555 label is a mistake or a later movement. Keep the attribution attached to the individual lot.

| Approximately 70 hours

|-

| escapement

| Chronergy

|-

| hairspring / shock

| Blue Parachrom / Paraflex

|-

| documented fitment here

| Datejust, Sea-Dweller and Submariner Date families

|}

Rolex introduced Cal. 3235 in 2015. It is the date-bearing member of the same generation as Cal. 3230, with a Chronergy escapement, blue Parachrom hairspring, Paraflex protection and approximately 70 hours of reserve. Rolex's brochures describe the date as instantaneous and the watch as COSC-certified and retested after casing to Rolex's tighter standard. [https://content.rolex.com/dam/media/brochures/datejust/m126333-0010.pdf Rolex, Datejust 41 brochure]

=== Cal. 3255 ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

! value

|-

| type

| Automatic, day and date

|-

| frequency

| 28,800 vph (4 Hz)

|-

| power reserve

| Approximately 70 hours

|-

| escapement

| Chronergy

|-

| hairspring / shock

| Blue Parachrom / Paraflex

|-

| documented fitment here

| Day-Date 40 and Day-Date 36

|}

Rolex introduced Cal. 3255 in 2015 for the Day-Date 40 and later Day-Date 36. The movement provides rapid-setting day and date displays, a Chronergy escapement, blue Parachrom hairspring, Paraflex shock absorbers and approximately 70 hours of reserve. It replaced Cal. 3156 in the Day-Date II successor generation; the 36mm Cal. 3155 remained a separate earlier movement. [https://newsroom-content.rolex.com/-/media/project/rolex/newsroom/rolex/rolex-newsroom-int/about-rolex/history-of-rolex/02_rolex_history_english_2021.pdf Rolex, History of Rolex, 2021] [https://newsroom-content.rolex.com/-/media/project/rolex/newsroom/rolex/rolex-newsroom-int/brochures/en/2022_information_sheet_day-date_en.pdf Rolex, Day-Date information sheet, 2022]

=== Cal. 3285 ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

! value

|-

| type

| Automatic GMT

|-

| frequency

| 28,800 vph (4 Hz)

|-

| power reserve

| Approximately 70 hours

|-

| functions

| Independent rapid-setting local hour, 24-hour display, instantaneous date

|-

| escapement

| Chronergy

|-

| hairspring / shock

| Blue Parachrom / Paraflex

|-

| documented fitment here

| GMT-Master II 126710, 126711, 126715, 126720 and related current references

|}

Rolex introduced Cal. 3285 in 2018 for the GMT-Master II. Its GMT hand remains independent of the local hour, the date changes instantaneously, and the movement combines Chronergy, a blue Parachrom hairspring, Paraflex protection and approximately 70 hours of reserve. [https://content.rolex.com/dam/media/brochures/gmt-master-ii/m126715chnr-0001.pdf Rolex, GMT-Master II brochure]

=== Cal. 4131 ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

! value

|-

| type

| Automatic chronograph

|-

| introduction

| 2023

|-

| power reserve

| Approximately 72 hours

|-

| chronograph

| Column wheel and vertical clutch

|-

| escapement / shock

| Chronergy / Paraflex

|-

| documented fitment here

| Daytona 126500 and 2023-onward gold and platinum Daytona references

|}

Rolex introduced Cal. 4131 in 2023 as the successor to Cal. 4130. The movement keeps the column wheel and vertical clutch and adds the Chronergy escapement, Paraflex shock absorbers, a blue Parachrom hairspring and Rolex Côtes de Genève decoration. Rolex gives an approximately 72-hour reserve. [https://newsroom.rolex.com/watches/new-watches-2024/cosmograph-daytona Rolex Newsroom, Cosmograph Daytona]

=== Cal. 4132 ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

! value

|-

| type

| Automatic chronograph

|-

| introduction

| 2023

|-

| special function

| 24-hour elapsed-time counter

|-

| documented fitment here

| Daytona 126529LN, the Le Mans anniversary model

|}

Cal. 4132 is the 4131 derivative used in the Le Mans anniversary Daytona. Rolex describes it as allowing the chronograph to count elapsed hours over 24 rather than the usual 12. The official history page does not publish a separate technical specification table, so the 4131 family specifications should not be copied into 4132 without a movement-specific source. [https://www.rolex.com/en-us/watches/cosmograph-daytona/beyond-the-racetrack Rolex, Cosmograph Daytona history]

== Day-Date ==

Day-Date calibers form their own family. Four-digit references set both calendar displays through the hands; five-digit references introduced quickset.

=== Cal. 1055 ===

{| class="wikitable" style="width:280px; font-size:90%;"

! detail

! value

|-

| type

| Automatic

|-

| jewels

| 25

|-

| frequency

| 18,000 vph (2.5 Hz)

|-

| power reserve

| 42h

|-

| escapement

| Straight-line lever

|-

| balance

| Monometallic

|-

| shock

| KIF

|}

Cal. 1055 is documented in the first four-digit Day-Date references, from 1956 to 1959: refs. 6510, 6511, 6611, 6612 and 6613. Its rhodium-plated bridges carry oeil-de-perdrix ("partridge-eye") circular graining rather than Côtes de Genève. Documented examples were adjusted to temperature and five positions.

Reference histories commonly date the 6611 to 1957 and associate it with the second, chronometer-certified 1055 generation. Phillips lists caliber 1055 on its 1956 gold 6611 and 1055B on its 1958 white-gold 6611B; catalogues do not use the suffix consistently. The dial wording changes to “Superlative Chronometer Officially Certified.”

6612 catalogues such as [https://www.phillips.com/detail/rolex/CH080115/43 Phillips lot 43], [https://www.bonhams.com/auction/20747/lot/353/ Bonhams lot 353], and [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend lot 67] show the same naming problem: Phillips (1958 platinum case 403,680), Bonhams (circa-1959 gold 6612/8), and Monaco Legend (1958 6612B examples) list Cal. 1055, while [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie’s Dubai lot 65] uses B1055 and other catalogues use 1055B. Keep the calibre label attached to the specific watch and source; those descriptions do not establish that every 6612 retained its original movement.

For examples catalogued as 6612B, Monaco Legend lists Cal. 1055 on yellow-gold case 384,933, white-gold case 394,866 and platinum case 403,679. Phillips lists B1055 on platinum case 446,052; Christie's Dubai uses B1055 while listing the case as 446,062. Treat these as lot-specific catalogue labels. The Dubai case number conflicts with Phillips and Sotheby's, which both give 446,052. [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-182 Monaco Legend, lot 182]; [https://www.monacolegendauctions.com/index.php/auction/exclusive-timepieces-36/lot-26 Monaco Legend, lot 26]; [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend, lot 67]; [https://www.phillips.com/detail/rolex/151223 Phillips, lot 155]; [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie's Dubai, lot 65].

The arrival of the free-sprung Microstella balance is disputed. The usual account places it with the 66xx revision, but an auction description identifies a first-generation 6511 as free-sprung. Neither generation has quickset or hacking.

Steel school-watch records create a separate problem: Antiquorum lists 1556 for a 2002 lot and 1066 for a 2013 lot, while Phillips describes later steel Day-Date prototypes with 1555-series movements. These are catalogue descriptions of disputed school/prototype watches, not confirmed 6611 production fitments. See [[Reference:6611|the 6611 record]] for the lot-level distinctions.

Auction catalogues also disagree on the movement fitted to ref. 6511. Phillips lists Cal. 1555 for case 111,654; Phillips lot 41, Antiquorum lot 81, Bonhams lot 156, and Monaco Legend lots 22 and 220 list Cal. 1055. The lot descriptions do not establish whether the 1555 label is a mistake or a later movement. Keep the attribution attached to the individual lot.

=== Cal. 1555 ===

Line 2,488:

Line 2,689:

|}

Cal. 3055 powered ~~the~~ refs. 18038, 18048, 18078 and early 18238 ~~from 1977 to 1988~~. It introduced quickset for the date, while the day still advanced through the motion of the hands. The balance cock provides the usual visual distinction from Cal. 3155, which uses a full transversal bridge. Common references give a height of 6.3mm, but Rolex's parts diagram specifies 7.11mm.

Cal. 3055 powered refs. 18038, 18039, 18048, 18049, 18078, 18079 and early 18238 in the 1977–1988 generation. It introduced quickset for the date, while the day still advanced through the motion of the hands. The balance cock provides the usual visual distinction from Cal. 3155, which uses a full transversal bridge. Common references give a height of 6.3mm, but Rolex's parts diagram specifies 7.11mm.

Line 2,659:

Line 2,860:

== Related but not Rolex ==

Gruen Cal. 877 and the Bubbleback-era "9¾ ligne" description are often misidentified as Rolex calibers. Gruen's Cal. 877, used in the Techni-Quadron, is an Aegler-built architectural sibling of Cal. 300 sold under Gruen's name in the United States. It was never a Rolex commercial number. A Bubbleback-era "9¾ ligne" description records only the movement's size class, not a distinct caliber designation.

Gruen Cal. 877 and the Bubbleback-era "9¾ ligne" description are often misidentified as Rolex calibers. Gruen's Cal. 877, used in the Techni-Quadron, is an Aegler-built architectural sibling of Cal. 300 sold under Gruen's name in the United States. It was never a Rolex commercial number. A Bubbleback-era "9¾ ligne" description records only the movement's size class, not a distinct caliber designation. The three circa-1940 Christie’s ref. 3064 catalogues reviewed for this audit use the same size-class wording and do not name a caliber; keep the 3064 movement attribution tied to those lot descriptions.

+== Sources ~~by caliber~~ ==

== Sources ==

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-63 Antiquorum, ref. 6567, 1956, Cal. 1030]

* [https://www.adams.ie/W103-lot-33-ROLEX-REF-1022-OYSTER-PERPETUAL-18K-YELLOW-GOLD-FLORENTINE-FINISH-CASE-A?auction_no=W103&page_no=3&sort_by=lot_no Adams, ref. 1022, 2025, Cal. 1560]

* [https://images3.bonhams.com/original?src=Images%2Flive%2F2015-04%2F23%2FS-22886-0-1.pdf Bonhams, ref. 1022, 2015, Cal. 1560]

* [https://www.pandolfini.it/it/asta-0036-1/orologio-da-rolex-oyster-perpetual-ref-1022--201405270143200 Pandolfini, ref. 1022, 2014, Cal. 1560]

* [https://www.tajan.com/auction-lot/rolex-oyster-perpetual-ref-1022-vers-1964-montre-_FA27968B44 Tajan, ref. 1022, 2014, automatic movement; caliber not stated]

* [https://shop.hodinkee.com/products/1963-rolex-oyster-perpetual-ref-1022-florentine-finish HODINKEE Shop, ref. 1022, 1963, Cal. 1560]

* [https://www.sothebys.com/en/buy/auction/2023/important-watches-online/prince-imperial-reference-1645-a-rolesium-steel Sotheby’s, 2023, Prince Imperial 1645, lot 331]

* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-1645-prince-imperial-lot-357-321 Antiquorum, 2022, Prince Imperial 1645, lot 321]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-113-16 Antiquorum, 2006, Prince Imperial 1645, lot 16]

* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-1645-lot-320-31 Antiquorum, 2019, Prince Imperial 1645, lot 31]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-266-70 Antiquorum, 2012, Prince Imperial 1645, lot 70]

The map below links each movement entry with the registry sources used for its summary fields. A link supports the section as a whole; disputed fields remain qualified in the prose. Calibers without an entity record remain covered by the general source list below.

~~{| class="wikitable sortable"~~

~~! Caliber !! Registry sources~~

|}

* [https://www.phillips.com/detail/rolex/CH080115/40 Phillips, 2015, ref. 6511 case 111,654, movement listed as 1555]

* [https://www.phillips.com/detail/rolex/CH080115/41 Phillips, 2015, ref. 6511 case 134,692, movement listed as 1055]

~~== Sources ==~~

* [https://www.phillips.com/detail/rolex/CH080115/50 Phillips, 2015, 6611 case 214,124, caliber 1055]

* [https://www.phillips.com/detail/rolex/CH080515/154 Phillips, 2015, 6611B case 401,546, caliber 1055B]

Line 2,726:

Line 2,931:

* [https://www.emmywatch.com EmmyWatch — vintage restoration movement photography]

* [https://monochrome-watches.com/complete-history-of-the-rolex-milgauss/ Monochrome — Complete History of the Rolex Milgauss]

* [https://www.christies.com/en/lot/lot-6067487 Christie’s, ref. 6543 case 145'111, Cal. 1080]

* [https://www.christies.com/lot/lot-5612347 Christie’s, ref. 6543 case 145'159, Cal. 1065]

* [https://revolutionwatch.com/rolex-milgauss-one-in-a-thousand/ Revolution, Milgauss movement and 6543 history]

* [https://www.sothebys.com/en/auctions/ecatalogue/2018/important-watches-n09952/lot.256.html Sotheby’s, 6541 case 412'479, Cal. 1080]

* [https://www.phillips.com/detail/rolex/206388 Phillips, same case and movement number, Cal. 1055]

* [https://www.robbreport.com/style/watch-collector/most-expensive-rolex-watches-ever-sold-at-auction/ Robb Report — The Most Expensive Rolex Watches Ever Sold at Auction] (Sotheby's Mercedes Gleitze Oyster, November 2025)

* [https://catalog.antiquorum.swiss Antiquorum — auction lot catalogue]

Line 2,749:

Line 2,959:

* [https://www.phillips.com/detail/rolex/CH080515/284 Phillips Geneva, 2015, ref. 6075 case 714440]: catalogued as A.296, 18 jewels.

* [https://www.christies.com/en/lot/lot-6042730 Christie’s, ref. 6075 case 699455]: catalogued as A.295.

* [https://live.mortonsubastas.com/en/online-auctions/morton-subastas/reloj-rolex-vintage-oyster-perpetual-en-acero-y-chapa-ref-1024-ca-1965---1966-movimiento-autom-tico-6579392 Morton Subastas, ref. 1024, 2024, Cal. 1560]

* [https://www.waddingtons.ca/auction/wrist-pocket-watches-dec-12-2024/gallery/lot/5/ Waddington's, ref. 1024, 2024, Cal. 1560]

* [https://www.dorotheum.com/de/l/5280014/ Dorotheum, ref. 1024, 2018, Cal. 1570]

* [https://www.phillips.com/detail/rolex/HK080121/904 Phillips, ref. 1024, 2021, Cal. 1570]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-22 Antiquorum, ref. 1010/1011, 1960, Cal. 1560, case 576171]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-213-465 Antiquorum, ref. 1010/1011, 1962, Cal. 1560, case 933961]

* [https://jewelry.ha.com/itm/timepieces/wristwatch/rolex-ref-1010-vintage-gold-oyster-perpetual-original-box-and-papers-circa-1962/a/5049-60215.s Heritage Auctions, ref. 1010, circa 1962, Cal. 1560, case 646320]

* [https://images3.bonhams.com/original?src=Images%2Flive%2F2015-04%2F23%2FS-22886-0-1.pdf Bonhams, ref. 1010, circa 1967, Cal. 1560, case 1659430]

* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-1010-oyster-perpetual-lot-334-19 Antiquorum, ref. 1010, circa 1968, Cal. 1570, case 1,960,000]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-45 Antiquorum, ref. 1011, 1960, Cal. 1560, case 546423]

* [https://www.christies.com/lot/lot-5496491 Christie’s, ref. 1011 case 692498, circa 1962, Cal. 1570]

* [https://jewelry.ha.com/itm/timepieces/wristwatch/rolex-ref-1011-bombe-lugs-14k-gold-oyster-perpetual/a/171226-74030.s Heritage, ref. 1011, Cal. 1560, 2012]

* [https://www.waddingtons.ca/?p=54274 Waddington’s, ref. 1011, Eaton’s presentation dial, Cal. 1520]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-203-530 Antiquorum, ref. 6094/6294, 2008, lot 530]

* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-242-134 Antiquorum, ref. 6094, 2010, lot 134]

* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-tropical-lot-262-291 Antiquorum, ref. 6094, 2012, lot 291]

* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-oysterdate-precision-lot-313-138 Antiquorum, ref. 6094, 2018, lot 138]

@@ Line 19: / Line 19: @@
 <div class="rp-era"><div class="rp-era-name">Oyster / Oysterdate Precision</div><div class="rp-chips">[[#cal-1210|1210]] [[#cal-1215|1215]] [[#cal-1216|1216]] [[#cal-1220|1220]] [[#cal-1225|1225]] [[#cal-1200|1200]]</div></div>
 <div class="rp-era"><div class="rp-era-name">Vintage sport (1950s–80s)</div><div class="rp-chips">[[#cal-1030|1030]] [[#cal-1035|1035]] [[#cal-1036|1036]] [[#cal-1065|1065]] [[#cal-1066|1066]] [[#cal-1530|1530]] [[#cal-1520|1520]] [[#cal-1535|1535]] [[#cal-1525|1525]] [[#cal-1560|1560]] [[#cal-1565|1565]] [[#cal-1570|1570]] [[#cal-1575|1575]]</div></div>
-<div class="rp-era"><div class="rp-era-name">Modern sport (1988–2023 coverage)</div><div class="rp-chips">[[#cal-3000|3000]] [[#cal-3035|3035]] [[#cal-3075|3075]] [[#cal-3085|3085]] [[#cal-3130|3130]] [[#cal-3132|3132]] [[#cal-3135|3135]] [[#cal-3175|3175]] [[#cal-3185|3185]] [[#cal-3186|3186]] [[#cal-3187|3187]]</div></div>
+<div class="rp-era"><div class="rp-era-name">Modern sport (1988–2023 coverage)</div><div class="rp-chips">[[#cal-3000|3000]] [[#cal-3035|3035]] [[#cal-3075|3075]] [[#cal-3085|3085]] [[#cal-3130|3130]] [[#cal-3132|3132]] [[#cal-3135|3135]] [[#cal-3175|3175]] [[#cal-3185|3185]] [[#cal-3186|3186]] [[#cal-3187|3187]] [[#cal-3230|3230]] [[#cal-3235|3235]] [[#cal-3285|3285]]</div></div>
-<div class="rp-era"><div class="rp-era-name">Milgauss</div><div class="rp-chips">[[#cal-1580|1580]] [[#cal-3131|3131]]</div></div>
+<div class="rp-era"><div class="rp-era-name">Milgauss</div><div class="rp-chips">[[#cal-1080|1080]] [[#cal-1580|1580]] [[#cal-3131|3131]]</div></div>
 <div class="rp-era"><div class="rp-era-name">Early chronograph</div><div class="rp-chips">[[#cal-13|13]]</div></div>
-<div class="rp-era"><div class="rp-era-name">Daytona chronograph</div><div class="rp-chips">[[#cal-72|72]] [[#cal-72a|72A]] [[#cal-72b|72B]] [[#cal-722|722]] [[#cal-722-1|722-1]] [[#cal-727|727]] [[#cal-4030|4030]] [[#cal-4130|4130]]</div></div>
+<div class="rp-era"><div class="rp-era-name">Daytona chronograph</div><div class="rp-chips">[[#cal-72|72]] [[#cal-72a|72A]] [[#cal-72b|72B]] [[#cal-722|722]] [[#cal-722-1|722-1]] [[#cal-727|727]] [[#cal-4030|4030]] [[#cal-4130|4130]] [[#cal-4131|4131]] [[#cal-4132|4132]]</div></div>
-<div class="rp-era"><div class="rp-era-name">Day-Date</div><div class="rp-chips">[[#cal-1055|1055]] [[#cal-1555|1555]] [[#cal-1556|1556]] [[#cal-1566|1566]] [[#cal-3055|3055]] [[#cal-3155|3155]] [[#cal-3156|3156]]</div></div>
+<div class="rp-era"><div class="rp-era-name">Day-Date</div><div class="rp-chips">[[#cal-1055|1055]] [[#cal-1555|1555]] [[#cal-1556|1556]] [[#cal-1566|1566]] [[#cal-3055|3055]] [[#cal-3155|3155]] [[#cal-3156|3156]] [[#cal-3255|3255]]</div></div>
 <div class="rp-era"><div class="rp-era-name">Oysterquartz</div><div class="rp-chips">[[#cal-5035|5035]] [[#cal-5055|5055]]</div></div>
 </div>
@@ Line 40: / Line 40: @@
 == Early chronograph movement
-The early Oyster chronograph references use Valjoux ébauches, with Rolex caliber designations that should be kept distinct from the maker’s base number. Available auction records support a limited Cal. 13 / Valjoux 23-family entry; they do not establish that every early Rolex chronograph used the same execution.
+The early Oyster chronograph references use Valjoux ébauches, with Rolex caliber designations that should be kept distinct from the maker’s base number. Available auction records support a limited Cal. 13 / Valjoux 23-family entry. That evidence concerns the 3525 and does not identify every early Rolex chronograph movement.
+Ref. [[Reference:2021|2021]] is a pre-Oyster monopusher. Published descriptions give movement sizes from 13 to 16½ lignes; Uhrenkosmos names a Valjoux VZ in one early monopusher, while auction catalogues describe different executions. The available records do not support a reference-wide caliber assignment. Keep these descriptions separate from the Cal. 13 entry below. [[https://www.uhrenkosmos.com/rolex-daytona-seine-technik-und-geschichte/ Uhrenkosmos, early monopusher movement]] [[https://www.phillips.com/detail/rolex/115419 Phillips, case 12'010]] [[https://www.cambiaste.com/it/asta-0795/rolex---rarissimo-cronografo-due-contatori-da-polso-monopulsante-in-ac-270066 Cambi, steel case 14xxx]]
 <span id="cal-13"></span>
@@ Line 70: / Line 72: @@
 Prince grades run Prima &rarr; Extra Prima &rarr; Ultra Prima, with higher jewel counts, more adjustment positions, and stricter chronometer testing. Only Extra Prima and Ultra Prima watches carry "Chronometer" or "Observatory" dial marks. Rolex submitted Prince movements to the National Physical Laboratory at Kew for rate certificates independent of the Swiss Bureaux Officiels Suisse de Contrôle. Its often-cited 1914 Class A Kew certificate belongs to an earlier ladies' wristwatch movement, while Prince testing at Kew-Teddington began in 1928.
+The Prince Imperial pocket watch, ref. [[Reference:1645|1645]], is also catalogued with shaped manual movements. Sotheby’s records a 17-jewel Class A Observatory movement, number 1,000,823. Antiquorum describes other 1645 examples as 17-jewel Ultra Prima or Observatory movements, measured at 14½, 16½ and 17 lignes. These are separate watches; the catalogues do not establish a numbered caliber sequence.
 <span id="cal-300"></span>
@@ Line 182: / Line 186: @@
 The architecture of Cal. 360 is disputed. Christie's describes a 1938 ref. 2835 "Prince Elegant" with a tonneau-shaped 15-jewel movement, and Charles Jarman's ''The Rolex Reference Guide'' (4th edition) calls Cal. 360 a manual, small-seconds, tonneau-shaped movement with a SuperBalance. Watch Doctor’s online chart instead lists a rectangular, 18-jewel movement measuring 18 × 27mm. The page does not identify an underlying Rolex document.
-Jarman dates Cal. 360 to 1937. The expansion of the HW designation remains unconfirmed; it should be retained as a designation rather than expanded to Hans Wilsdorf. The differing shape and jewel descriptions need comparison with the movement in the individual watch.
+Jarman dates Cal. 360 to 1937. The expansion of the HW designation remains unconfirmed; it should be retained as a designation rather than expanded to Hans Wilsdorf. The differing shape and jewel descriptions need comparison with the movement in the individual watch. Ineichen’s 2016 catalogue attributes C.360 to a Prince ref. 1880 and describes a nickel-plated lever movement. That is one lot-level attribution; it does not resolve the conflicting descriptions above. [https://ineichen.com/upload/iblock/83c/fnnltq7byndm2n2lwa14zfgz3qzl1tuc.pdf Ineichen, Auction 164, lot 133]
 <span id="cal-510"></span>
@@ Line 289: / Line 293: @@
 <span id="bubbleback-family"></span>
+== Early manual-wind Oyster examples ==
+The early cushion-case Oyster references used manual movements, but the available catalogue descriptions do not support one movement assignment for every reference. For [[Reference:1069|ref. 1069]], Antiquorum describes a 15-jewel 11-ligne manual movement on its 2003 example; Christie's describes an unnamed 15-jewel lever movement, and a dealer-photographed example shows a 17-jewel Rolex movement. Keep each description with its watch. Aste Bolaffi's Marconi Oyster has a 15-jewel FHF 30-based movement and the number 1069 on its case, but the catalogue does not identify that number as the reference. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-41-480 Antiquorum 2003]; [https://www.christies.com/lot/lot-3892839 Christie's]; [https://www.1stdibs.com/jewelry/watches/wrist-watches/rolex-nickel-silver-cushion-shaped-oyster-original-dial/id-j_18189072/ dealer photo set]; [https://www.astebolaffi.it/en/lot/268/87/detail Aste Bolaffi 2022]
+For [[Reference:1072|ref. 1072]], Antiquorum describes 10-ligne, 18-jewel movements in two examples. Bonhams calls a separate example a 15-jewel Prima. Cool Auction labels the movement Cal. 10½ and reports 15 jewels, 18,000 beats per hour and a maximum 38-hour reserve on a Bucherer-signed watch. The same dealer attributes a Superbalance and Breguet hairspring to that movement. Hess Fine Auctions reports a manual 15-jewel movement in its 2023 lot. Watch Collecting describes another example as manual-wind but gives no caliber or jewel count. Toovey’s title calls its circa-1938 example Ultra Prima but gives no movement specification. The Cool Auction caliber label has no corroboration in the other records; the lots do not establish a single movement assignment or grade across the reference. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-96-82 Antiquorum, Hong Kong, 1997]; [https://www.collectorsquare.com/en/watches/rolex/prima/lpi Antiquorum and Bonhams archive]; [https://www.cool-auction.net/gallery/23866/ Cool Auction]; [https://www.hessfineauctions.com/auction-lot/superior-rolex-oyster-1072-large-cushion-vintage_98542e8bd8 Hess Fine Auctions, lot 3211]; [https://collecting.com/for-sale/1938-rolex-oyster-2 Watch Collecting]; [https://www.tooveys.com/lots/613066/a-rolex-oyster-ultra-prima-chrome-cushion-cased-gentlemans-wristwatch Toovey’s]
+For [[Reference:1073|ref. 1073]], Antiquorum names a 10½-ligne Extra Prima movement with 15 jewels. Christie’s calls its 15-jewel movement Prima; Bonhams calls another example Ultra Prima. These lot descriptions do not establish a shared caliber number or grade across the reference. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-15-258 Antiquorum]; [https://www.christies.com/lot/lot-811717 Christie’s]; [https://www.collectorsquare.com/en/watches/rolex/oyster/ref-rolex-1073/lpi Bonhams archive]
 == Bubbleback and early automatic ==
@@ Line 386: / Line 398: @@
 The Field Manual also lists Cal. 630 against the 3372 suffix variants. Antiquorum explicitly names Cal. 630 in a 3372 with centre seconds ([New York lot 436](https://catalog.antiquorum.swiss/en/lots/rolex-lot-23-436)). The same manual lists subsidiary seconds for one 3372/3 entry, while Christie's catalogue describes a 3372 with small seconds and a 9¾-ligne, 17-jewel movement but gives no caliber number ([case 474309](https://www.christies.com/lot/rolex-oyster-perpetual-chronometre-bubble-back-ref-5091692/?intObjectID=5091692&lid=1)). Keep those statements tied to their sources; they do not establish a Cal. 630 small-seconds variant.
+Henrik Korpela identifies Cal. 630 NA in one gold watch catalogued as ref. [[Reference:6074|6074]]; its movement number is 56567. Korpela's photographs show 6030 and 6031 scratched out on the caseback before 6074 was stamped over them ([https://watchesbysjx.com/2015/05/explained-restoring-a-1950s-rolex-oyster-perpetual-ref-6074.html SJX restoration]). Antiquorum's 1992 platinum 6074 lot gives a 9¾-ligne, 17-jewel movement with antishock but names no caliber ([https://catalog.antiquorum.swiss/en/lots/rolex-lot-146-67 lot 67]). Keep each description attached to its watch; the records do not establish a reference-wide caliber assignment.
 <span id="cal-635"></span>
@@ Line 391: / Line 405: @@
 Cal. 635 belongs to the early automatic family related to Cal. 620. General movement references describe a subsidiary-seconds layout, 17 jewels and a larger movement than the 9¾-ligne measurements in two 3130 auction entries. Antiquorum catalogued 3130 cases 54932 and 474617 with Cal. 635, 19 jewels, 9¾ lignes and subsidiary seconds ([lot 256](https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-256); [lot 169](https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-169)). Christie's identified case 443093 as Cal. 635 with 19 jewels but centre seconds ([2007 lot 2858](https://www.christies.com/en/lot/lot-5008631)). The latter catalogue description conflicts with the usual seconds layout. Without a visible caliber stamp, keep the centre-seconds attribution attached to that lot; do not treat it as a confirmed Cal. 635 variant.
+Ref. [[Reference:1925|1925]] lots name Prima or Ultra Prima grades. Antiquorum describes a 9′′′, 15-jewel Prima; Christie’s names Prima on its 1928 example and Ultra Prima on a 1930s octagonal watch; Sterling Vault records a 15-jewel Ultra Prima. The auction record supplies grade names rather than a numeric caliber assignment. Antiquorum also describes a 1948 ref. [[Reference:2081|2081]] with a 10-ligne, 15-jewel Prima; that lot does not name a caliber. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-203-675 Antiquorum, lot 675]
 <span id="cal-105-hunter"></span>
@@ Line 403: / Line 419: @@
 |-
 | jewels
-| 17–18
+| 15–18
 |-
 | frequency
@@ Line 421: / Line 437: @@
 |}
-This Aegler-supplied 10½-ligne hand-wound family uses the 700/710 architecture. It has a straight-line lever escapement, monometallic Superbalance adjusted to six positions, self-compensating Breguet balance spring, and swan-neck micrometer regulator, with no documented shock protection. The movement powers the original Air-King 4925 and its Air-Lion, Air-Tiger, and Air-Giant siblings, including the sub-seconds 4365, mid-size 4444, and 4647 Hunter Precision. Its architecture links the pre-war Prince and Bubbleback movements with the post-war automatic Cal. 1030. Cal. 700 and 710 are hand-wound movements; Cal. 720 belongs to the automatic branch. White’s *The Vintage Rolex Field Manual* maps [[Reference:5031|ref. 5031]] to Cal. 710 in a reference table, but auction catalogues describe 5031 examples as automatic date watches. Christie’s [https://www.christies.com/en/lot/lot-204100 listing] records movement number 37519 but no caliber; Antiquorum’s [https://catalog.antiquorum.swiss/en/lots/rolex-lot-120-203 1995], [https://catalog.antiquorum.swiss/en/lots/rolex-lot-53-191 1999] and [https://catalog.antiquorum.swiss/en/lots/rolex-lot-222-285 2009] entries do not name a caliber and report differing sizes and jewel counts. Sotheby’s 2020 and 2022 entries say only “automatic.” The available records do not resolve the conflict, so the 5031 is not assigned to Cal. 710, A.295, 740, or 745 here.
+This Aegler-supplied 10½-ligne hand-wound family uses the 700/710 architecture. It has a straight-line lever escapement, monometallic Superbalance adjusted to six positions, self-compensating Breguet balance spring, and swan-neck micrometer regulator, with no documented shock protection. Antiquorum names Cal. 700 in its catalogue for ref. [[Reference:3358|3358]], case 51,419, with 18 jewels; its ref. [[Reference:2081|2081]] case 599,744 lot names the same caliber and grade but records 15 jewels. The discrepancy is unresolved, so the jewel count is left unspecified here. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-225 Antiquorum, ref. 3358] [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-226 Antiquorum, ref. 2081] The movement powers the original Air-King 4925 and its Air-Lion, Air-Tiger, and Air-Giant siblings, including the sub-seconds 4365, mid-size 4444, and 4647 Hunter Precision. Its architecture links the pre-war Prince and Bubbleback movements with the post-war automatic Cal. 1030. Cal. 700 and 710 are hand-wound movements; Cal. 720 belongs to the automatic branch. White’s *The Vintage Rolex Field Manual* maps [[Reference:5031|ref. 5031]] to Cal. 710 in a reference table, but auction catalogues describe 5031 examples as automatic date watches. Christie’s [https://www.christies.com/en/lot/lot-204100 listing] records movement number 37519 but no caliber; Antiquorum’s [https://catalog.antiquorum.swiss/en/lots/rolex-lot-120-203 1995], [https://catalog.antiquorum.swiss/en/lots/rolex-lot-53-191 1999] and [https://catalog.antiquorum.swiss/en/lots/rolex-lot-222-285 2009] entries do not name a caliber and report differing sizes and jewel counts. Sotheby’s 2020 and 2022 entries say only “automatic.” The available records do not resolve the conflict, so the 5031 is not assigned to Cal. 710, A.295, 740, or 745 here.
 White’s reference table also maps [[Reference:6031|ref. 6031]] to Cal. 710, but the auction records describe automatic date watches. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-17-555 Antiquorum’s 2001 lot] and [https://catalog.antiquorum.swiss/en/lots/rolex-lot-25-143 2002 lot] list 10½ lignes and 19 jewels without naming a caliber; the latter combines refs. 6031 and 6074. [https://www.phillips.com/detail/rolex/160689 Phillips] records movement G3569, and [https://www.sothebys.com/en/buy/auction/2025/fine-watches-pf2570/oyster-perpetual-reference-6031-montre-bracelet-en?locale=en Sotheby’s] G9307, but neither names a caliber. The assignment remains unresolved.
@@ Line 671: / Line 687: @@
 Antiquorum gives 26 jewels for its Cal. 740 example. That count should be kept with the source's description. A different count in a reference table may reflect a counting convention or a different execution; the number alone does not settle which.
+Antiquorum also assigns Cal. 740 to manual-wind [[Reference:6094|ref. 6094]], usually with 17 jewels. Its 2008 lot labels the case 6094/6294; the 2010 and 2012 lots identify ref. 6094 alone. The 2018 listing for case 882812 calls the watch self-winding in its headline while the specification field gives Cal. 740. Keep these as lot-level attributions: the records do not establish that the 6094 Cal. 740 is the automatic 26-jewel movement documented here for ref. 4467. [https://catalog.antiquorum.swiss/en/lots/rolex-lot-203-530 Antiquorum, lot 530]; [https://catalog.antiquorum.swiss/en/lots/rolex-lot-242-134 Antiquorum, lot 134]; [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-tropical-lot-262-291 Antiquorum, lot 291]; [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-oysterdate-precision-lot-313-138 Antiquorum, lot 138].
 Surviving examples can have replacement movements or parts. A reference launch date should not be assigned automatically to the movement now inside a particular case.
@@ Line 842: / Line 860: @@
 Cal. 1215 uses a gradual date change rather than a direct quickset. The date begins moving before midnight and seats as the mechanism completes its cycle.
-Christie's places the ref. 6494 changeover between a circa-1956 example with Cal. 1210 and a circa-1958 example with 1215. Other documented fitments include the Speedking 6430, early 6694 production, and refs. 9996/9919. Refs. 6094 and 6294 used Cal. 740 and 790 respectively, rather than 1215.
+Christie's places the ref. 6494 changeover between a circa-1956 example with Cal. 1210 and a circa-1958 example with 1215. Other documented fitments include the Speedking 6430, early 6694 production, and refs. 9996/9919.
 <span id="cal-1216"></span>
@@ Line 1,036: / Line 1,056: @@
 |}
-Cal. 1030 is a bidirectionally wound automatic used in 1950s Oyster references. Its 5.85mm profile ended the domed Bubbleback caseback, while the cutaway "butterfly" rotor stamped ROLEX PERPETUAL PATENTED is the usual visual identifier. Finishing includes perlage on the rhodium-plated main plate, brushed bridges, polished screw heads and red anodized-aluminium reversing wheels. A conventional index regulates the movement; the visible regulator arm distinguishes it from the later free-sprung 1560 and 1570. Documented fitments include ref. 6098 from 1952, Submariners 6536, 6536-1 and 6538, Explorer 6610 and Air-King 6552. The same movement appeared in chronometer and non-chronometer watches.
+Cal. 1030 is a bidirectionally wound automatic used in 1950s Oyster references. Its 5.85mm profile ended the domed Bubbleback caseback, while the cutaway "butterfly" rotor stamped ROLEX PERPETUAL PATENTED is the usual visual identifier. Finishing includes perlage on the rhodium-plated main plate, brushed bridges, polished screw heads and red anodized-aluminium reversing wheels. A conventional index regulates the movement; the visible regulator arm distinguishes it from the later free-sprung 1560 and 1570. Documented fitments include ref. 6098 from 1952 and Oyster Perpetual 6567 from the 1950s, Submariners 6536, 6536-1 and 6538, Explorer 6610 and Air-King 6552. The same movement appeared in chronometer and non-chronometer watches.
 <span id="cal-1035"></span>
@@ Line 1,114: / Line 1,134: @@
 |}
-Cal. 1530 ran from 1957 to 1965. Its 17-, 25- and 26-jewel versions are concurrent market variants, not a chronological progression. Seventeen-jewel movements appear in a 1958-era ref. 5508, a 5500 and a 1011 Eaton, and Rolex’s Technical and Service Information, third edition, discusses the 1520 and 1530 families in its servicing instructions.
+Cal. 1530 ran from 1957 to 1965. Its 17-, 25- and 26-jewel versions are concurrent market variants, not a chronological progression. Seventeen-jewel movements appear in a 1958-era ref. 5508 and a 5500, and Rolex’s Technical and Service Information, third edition, discusses the 1520 and 1530 families in its servicing instructions.
 Cal. 1530 is the base for the 1520, 1560, 1570 and 1580. They share plates and many service parts, including interchangeable automatic-device bridges, so the engraved bridge number may not identify the movement beneath it. Balance-bridge and regulator form are more reliable.
@@ Line 1,128: / Line 1,148: @@
 The rotor changed from butterfly to half-moon during production. Later movements also gained blued automatic-bridge screws and coloured reversing wheels in place of brass-coloured gears. Rolex describes the red wheel finish as a hardening treatment for aluminium introduced in 1957; collector descriptions often call the wheels purple and Teflon-coated. Rotor and reversing-wheel form help date an example.
-The 1530 first entered the Submariner in ref. 5508, followed by 5510; neither was chronometer-rated at launch. It replaced the 10-series in non-chronometer watches, including Precision models, the Air-King, ref. 5504 "Super-Precision" Explorer and the Canadian Explorer-Date with Cal. 1535. Certified models such as the 6542 GMT, 6610 Explorer, Datejust and Day-Date retained 10xx calibers for longer. Strongly documented fitments include refs. 5508, 5510, 5512, 5513, 5500 and 5504. Single-lot support exists for 5501, 5502, 5506, 5516 and 5590/1011 Eaton. Bonhams listings for refs. 1002 and 1003 are internally inconsistent and remain unconfirmed. Bonhams lot 84 lists caliber 1530 in ref. 1003 case 573,835 and notes a chronometer certificate dated 22 December 1960. The catalogue is the evidence for this individual attribution; it does not resolve why common reference tables omit the 1530 for 1003.
+The 1530 first entered the Submariner in ref. 5508, followed by 5510; neither was chronometer-rated at launch. It replaced the 10-series in non-chronometer watches, including Precision models, the Air-King, ref. 5504 "Super-Precision" Explorer and the Canadian Explorer-Date with Cal. 1535. Certified models such as the 6542 GMT, 6610 Explorer, Datejust and Day-Date retained 10xx calibers for longer. Strongly documented fitments include refs. 5508, 5510, 5512, 5513, 5500 and 5504. Single-lot support exists for 5501, 5502, 5506 and 5516. Bonhams listings for refs. 1002 and 1003 are internally inconsistent and remain unconfirmed. Bonhams lot 84 lists caliber 1530 in ref. 1003 case 573,835 and notes a chronometer certificate dated 22 December 1960. The catalogue is the evidence for this individual attribution; it does not resolve why common reference tables omit the 1530 for 1003.
 Rolex specifies a 0.122–0.125mm mainspring for the 18,000-vph 1530 and 1560, against up to 0.125 or 0.128mm for the higher-beat 1520 and 1570. Early unjewelled barrel-bridge arbor holes can wear; Rolex prescribed closing the hole or reaming it for a jewel, while later production received a bushing. Rotor-axle wear is another known fault. On the 1560, a hard shock could push the hairspring into the regulator. Rolex supplied a safety pin free of charge and later made it standard, so both guarded and unguarded examples are correct.
@@ Line 1,264: / Line 1,284: @@
 Auction catalogues often label the date-equipped Cal. 1525 as Cal. 1520. Antiquorum does so on a 1972 ref. 5700, while describing the expected flat hairspring and index-regulated architecture. The chronometer-grade 1560 and 1570 use a Breguet overcoil and Microstella. The Cal. 1525 uses the index regulation associated with the uncertified 5700.
-Jewel counts of 17, 25 and 26 reflect parallel market executions. Rolex balance-assembly numbers confirm a flat hairspring for the 1520 and 1525, against a Breguet spring on the 1530 and Microstella on the 1560. The 1525 remains index-regulated.
+Jewel counts of 17, 25 and 26 reflect parallel market executions. Rolex balance-assembly numbers confirm a flat hairspring for the 1520 and 1525, against a Breguet spring on the 1530 and Microstella on the 1560. The 1525 remains index-regulated. Waddington’s identifies Cal. 1520, 26 jewels, in a circa-1965 Eaton’s ¼ Century Club watch catalogued as ref. 1011, case 1,301,143. See [[Reference:1011|ref. 1011]].
 <span id="cal-1560"></span>
@@ Line 1,295: / Line 1,315: @@
 |}
-Cal. 1560 arrived in 1959 as the chronometer-grade 15xx movement, with a free-sprung balance adjusted to temperature and five positions. Auction catalogues give both 25 and 26 jewels without establishing a pattern. Antiquorum usually describes a Breguet overcoil; its flat-hairspring description for one ref. 1502/1503 is an outlier.
+Cal. 1560 arrived in 1959 as the chronometer-grade 15xx movement, with a free-sprung balance adjusted to temperature and five positions. Auction catalogues give both 25 and 26 jewels without establishing a pattern. Antiquorum usually describes a Breguet overcoil; its flat-hairspring description for one ref. 1502/1503 is an outlier. The Oyster Perpetual ref. 1022 is documented with Cal. 1560 by Bonhams, Pandolfini, Adams, and HODINKEE; Tajan describes an automatic movement but names no caliber. Auction catalogues also identify Cal. 1560 in ref. 1024 examples dated circa 1965/66 and circa 1970. Antiquorum lists Cal. 1560 in a ref. 1011 dated 1960, case 546423, and in two lots jointly catalogued as refs. 1010/1011, dated 1960 and 1962. Heritage also lists Cal. 1560 in an undated ref. 1011 sold in 2012. Heritage and Bonhams list Cal. 1560 in individual ref. 1010 lots dated circa 1962 and circa 1967; Antiquorum lists Cal. 1570 in an individual ref. 1010 circa 1968. The Field Manual lists Cal. 1560 for ref. 1010. These records document both attributions; the changeover year remains open. See [[Reference:1010|ref. 1010]].
 Cal. 1560 uses free-sprung Microstella regulation; Cal. 1530 uses an index. Watches made from 1959 to 1965 were tested by the Bureaux Officiels de Contrôle de la Marche des Montres, usually under collective certificates and to a standard around −1/+10 seconds per day in five positions. COSC did not exist until September 1973, so describing an early 1560 as COSC-certified is anachronistic.
@@ Line 1,364: / Line 1,384: @@
 |}
-Cal. 1570 is the 19,800-vph revision of the 1560, introduced in 1965. One Artcurial ref. 1005 lot is catalogued with Cal. 1550, despite a chronometer-dial description; other 1005 catalogues list 1560 or 1570. This single lot does not establish a 1005 movement variant or resolve whether the movement is original. It retains the free-sprung Breguet overcoil and Microstella regulation, with adjustment to temperature and five positions. Family-wide bridge engraving causes date movements such as the 1575 in a ref. 1665 to appear marked 1570; the engraving alone does not identify the exact caliber.
+Cal. 1570 is the 19,800-vph revision of the 1560, introduced in 1965. Christie’s identifies Cal. 1570 in ref. 1011 case 692498, dated circa 1962; its lot chronology overlaps the ref. 1011 Cal. 1560 examples and does not establish a changeover. See [[Reference:1011|ref. 1011]]. One Artcurial ref. 1005 lot is catalogued with Cal. 1550, despite a chronometer-dial description; other 1005 catalogues list 1560 or 1570. This single lot does not establish a 1005 movement variant or resolve whether the movement is original. It retains the free-sprung Breguet overcoil and Microstella regulation, with adjustment to temperature and five positions. Family-wide bridge engraving causes date movements such as the 1575 in a ref. 1665 to appear marked 1570; the engraving alone does not identify the exact caliber. Phillips identifies Cal. 1570 in a circa-1985 ref. 1024, while Dorotheum lists it on a circa-1965/70 example; the auction dates overlap the Cal. 1560 records.
 The balance has four Microstella screws in two opposing pairs, not two. Rolex required equal adjustment within each pair to preserve poise. The larger pair changes rate by about two seconds per day and the smaller by about one. On this family the screws sit in the balance rim; the later 3135 platform moves its Microstella nuts to the inner rim.
@@ Line 1,958: / Line 1,978: @@
 == Milgauss ==
-Rolex introduced the documented Milgauss calibers about fifty years apart. Rolex adapted its contemporary sport movements for the Milgauss: Cal. 1580 derives from the 1530 platform, and Cal. 3131 from Cal. 3130.
+Auction catalogues assign Cal. 1080 to early Milgauss examples, though a later catalogue labels the same 6541 movement number Cal. 1055. Cal. 1580 derives from the 1530 platform; Cal. 3131 derives from Cal. 3130.
+<span id="cal-1080"></span>
+=== Cal. 1080 ===
+{| class="wikitable" style="width:280px; font-size:90%;"
+! detail
+! value
+|-
+| type
+| Automatic
+|-
+| jewels
+| 25 listed for Christie’s case 145'111 and Sotheby’s case 412'479
+|-
+| documented fitment
+| Milgauss 6543 and 6541 examples; one 6541 movement number carries conflicting 1080 / 1055 catalogue labels
+|-
+| base relationship
+| Revolution describes it as modified from Cal. 1030
+|}
+Christie’s lists Cal. 1080 in 6543 case 145'111. Revolution also assigns the caliber to the 6543 and describes a Cal. 1030 relationship. Sotheby’s called movement N726507 in 6541 case 412'479 Cal. 1080 in 2018; Phillips listed the same case and movement number as Cal. 1055 in 2026. The surviving catalogues document these watch-level labels, not a settled specification or changeover sequence.
 <span id="cal-1580"></span>
@@ Line 2,320: / Line 2,361: @@
 Parachrom was fitted from launch, but the blue version is variously dated between about 2005 and 2007 without a supporting Rolex document. Later examples were rated to Rolex's −2/+2 seconds-per-day standard after its introduction in 2015. Cal. 4130 continued through the ref. 116500LN until Cal. 4131 replaced it in March 2023.
-<span id="day-date-family"></span>
-== Day-Date ==
-Day-Date calibers form their own family. Four-digit references set both calendar displays through the hands; five-digit references introduced quickset.
+<span id="cal-3230"></span>
+=== Cal. 3230 ===
-<span id="cal-1055"></span>
-=== Cal. 1055 ===
-[[File:Cal 1055 movement.webp|thumb|right|220px|Cal. 1055, period parts-catalogue illustration, front and back|alt=Cal. 1055, period parts-catalogue illustration, front and back]]
 {| class="wikitable" style="width:280px; font-size:90%;"
 ! detail
@@ Line 2,333: / Line 2,369: @@
 |-
 | type
-| Automatic
+| Automatic, no date
 |-
-| jewels
+| frequency
-| 25
+| 28,800 vph (4 Hz)
 |-
-| frequency
+| power reserve
-| 18,000 vph (2.5 Hz)
+| Approximately 70 hours
 |-
-| power reserve
+| escapement
-| 42h
+| Chronergy
 |-
-| escapement
+| hairspring / shock
-| Straight-line lever
+| Blue Parachrom / Paraflex
 |-
-| balance
+| documented fitment here
-| Monometallic
+| 124060, 124270, 126000, 126900; catalogue conflicts for some 114300 lots are recorded above
-|-
+|}
-| shock
-| KIF
+Rolex introduced Cal. 3230 in 2020 as the no-date member of its newer movement generation. Rolex describes the movement with a Chronergy escapement, blue Parachrom hairspring, Paraflex shock absorbers and approximately 70 hours of reserve. The individual reference page remains the authority for a specific watch; catalogue attributions that conflict with Rolex product documentation are recorded as conflicts rather than silently normalized. [https://newsroom-content.rolex.com/-/media/project/rolex/newsroom/rolex/rolex-newsroom-int/about-rolex/history-of-rolex/02_rolex_history_english_2021.pdf Rolex, History of Rolex, 2021]
-|}
+<span id="cal-3235"></span>
-Cal. 1055 is documented in the first four-digit Day-Date references, from 1956 to 1959: refs. 6510, 6511, 6611, 6612 and 6613. Its rhodium-plated bridges carry oeil-de-perdrix ("partridge-eye") circular graining rather than Côtes de Genève. Documented examples were adjusted to temperature and five positions.
+=== Cal. 3235 ===
+{| class="wikitable" style="width:280px; font-size:90%;"
-Reference histories commonly date the 6611 to 1957 and associate it with the second, chronometer-certified 1055 generation. Phillips lists caliber 1055 on its 1956 gold 6611 and 1055B on its 1958 white-gold 6611B; catalogues do not use the suffix consistently. The dial wording changes to “Superlative Chronometer Officially Certified.”
+! detail
+! value
-catalogues such as [https://www.phillips.com/detail/rolex/CH080115/43 Phillips lot 43], [https://www.bonhams.com/auction/20747/lot/353/ Bonhams lot 353], and [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend lot 67] show the same naming problem: Phillips (1958 platinum case 403,680), Bonhams (circa-1959 gold 6612/8), and Monaco Legend (1958 6612B examples) list Cal. 1055, while [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie’s Dubai lot 65] uses B1055 and other catalogues use 1055B. Keep the calibre label attached to the specific watch and source; those descriptions do not establish that every 6612 retained its original movement.
+|-
+| type
-For examples catalogued as 6612B, Monaco Legend lists Cal. 1055 on yellow-gold case 384,933, white-gold case 394,866 and platinum case 403,679. Phillips lists B1055 on platinum case 446,052; Christie's Dubai uses B1055 while listing the case as 446,062. Treat these as lot-specific catalogue labels. The Dubai case number conflicts with Phillips and Sotheby's, which both give 446,052. [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-182 Monaco Legend, lot 182]; [https://www.monacolegendauctions.com/index.php/auction/exclusive-timepieces-36/lot-26 Monaco Legend, lot 26]; [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend, lot 67]; [https://www.phillips.com/detail/rolex/151223 Phillips, lot 155]; [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie's Dubai, lot 65].
+| Automatic, date
+|-
-The arrival of the free-sprung Microstella balance is disputed. The usual account places it with the 66xx revision, but an auction description identifies a first-generation 6511 as free-sprung. Neither generation has quickset or hacking.
+| frequency
+| 28,800 vph (4 Hz)
-Steel school-watch records create a separate problem: Antiquorum lists 1556 for a 2002 lot and 1066 for a 2013 lot, while Phillips describes later steel Day-Date prototypes with 1555-series movements. These are catalogue descriptions of disputed school/prototype watches, not confirmed 6611 production fitments. See [[Reference:6611|the 6611 record]] for the lot-level distinctions.
+|-
+| power reserve
-Auction catalogues also disagree on the movement fitted to ref. 6511. Phillips lists Cal. 1555 for case 111,654; Phillips lot 41, Antiquorum lot 81, Bonhams lot 156, and Monaco Legend lots 22 and 220 list Cal. 1055. The lot descriptions do not establish whether the 1555 label is a mistake or a later movement. Keep the attribution attached to the individual lot.
+| Approximately 70 hours
+|-
+| escapement
+| Chronergy
+|-
+| hairspring / shock
+| Blue Parachrom / Paraflex
+|-
+| documented fitment here
+| Datejust, Sea-Dweller and Submariner Date families
+|}
+Rolex introduced Cal. 3235 in 2015. It is the date-bearing member of the same generation as Cal. 3230, with a Chronergy escapement, blue Parachrom hairspring, Paraflex protection and approximately 70 hours of reserve. Rolex's brochures describe the date as instantaneous and the watch as COSC-certified and retested after casing to Rolex's tighter standard. [https://content.rolex.com/dam/media/brochures/datejust/m126333-0010.pdf Rolex, Datejust 41 brochure]
+<span id="cal-3255"></span>
+=== Cal. 3255 ===
+{| class="wikitable" style="width:280px; font-size:90%;"
+! detail
+! value
+|-
+| type
+| Automatic, day and date
+|-
+| frequency
+| 28,800 vph (4 Hz)
+|-
+| power reserve
+| Approximately 70 hours
+|-
+| escapement
+| Chronergy
+|-
+| hairspring / shock
+| Blue Parachrom / Paraflex
+|-
+| documented fitment here
+| Day-Date 40 and Day-Date 36
+|}
+Rolex introduced Cal. 3255 in 2015 for the Day-Date 40 and later Day-Date 36. The movement provides rapid-setting day and date displays, a Chronergy escapement, blue Parachrom hairspring, Paraflex shock absorbers and approximately 70 hours of reserve. It replaced Cal. 3156 in the Day-Date II successor generation; the 36mm Cal. 3155 remained a separate earlier movement. [https://newsroom-content.rolex.com/-/media/project/rolex/newsroom/rolex/rolex-newsroom-int/about-rolex/history-of-rolex/02_rolex_history_english_2021.pdf Rolex, History of Rolex, 2021] [https://newsroom-content.rolex.com/-/media/project/rolex/newsroom/rolex/rolex-newsroom-int/brochures/en/2022_information_sheet_day-date_en.pdf Rolex, Day-Date information sheet, 2022]
+<span id="cal-3285"></span>
+=== Cal. 3285 ===
+{| class="wikitable" style="width:280px; font-size:90%;"
+! detail
+! value
+|-
+| type
+| Automatic GMT
+|-
+| frequency
+| 28,800 vph (4 Hz)
+|-
+| power reserve
+| Approximately 70 hours
+|-
+| functions
+| Independent rapid-setting local hour, 24-hour display, instantaneous date
+|-
+| escapement
+| Chronergy
+|-
+| hairspring / shock
+| Blue Parachrom / Paraflex
+|-
+| documented fitment here
+| GMT-Master II 126710, 126711, 126715, 126720 and related current references
+|}
+Rolex introduced Cal. 3285 in 2018 for the GMT-Master II. Its GMT hand remains independent of the local hour, the date changes instantaneously, and the movement combines Chronergy, a blue Parachrom hairspring, Paraflex protection and approximately 70 hours of reserve. [https://content.rolex.com/dam/media/brochures/gmt-master-ii/m126715chnr-0001.pdf Rolex, GMT-Master II brochure]
+<span id="cal-4131"></span>
+=== Cal. 4131 ===
+{| class="wikitable" style="width:280px; font-size:90%;"
+! detail
+! value
+|-
+| type
+| Automatic chronograph
+|-
+| introduction
+| 2023
+|-
+| power reserve
+| Approximately 72 hours
+|-
+| chronograph
+| Column wheel and vertical clutch
+|-
+| escapement / shock
+| Chronergy / Paraflex
+|-
+| documented fitment here
+| Daytona 126500 and 2023-onward gold and platinum Daytona references
+|}
+Rolex introduced Cal. 4131 in 2023 as the successor to Cal. 4130. The movement keeps the column wheel and vertical clutch and adds the Chronergy escapement, Paraflex shock absorbers, a blue Parachrom hairspring and Rolex Côtes de Genève decoration. Rolex gives an approximately 72-hour reserve. [https://newsroom.rolex.com/watches/new-watches-2024/cosmograph-daytona Rolex Newsroom, Cosmograph Daytona]
+<span id="cal-4132"></span>
+=== Cal. 4132 ===
+{| class="wikitable" style="width:280px; font-size:90%;"
+! detail
+! value
+|-
+| type
+| Automatic chronograph
+|-
+| introduction
+| 2023
+|-
+| special function
+| 24-hour elapsed-time counter
+|-
+| documented fitment here
+| Daytona 126529LN, the Le Mans anniversary model
+|}
+Cal. 4132 is the 4131 derivative used in the Le Mans anniversary Daytona. Rolex describes it as allowing the chronograph to count elapsed hours over 24 rather than the usual 12. The official history page does not publish a separate technical specification table, so the 4131 family specifications should not be copied into 4132 without a movement-specific source. [https://www.rolex.com/en-us/watches/cosmograph-daytona/beyond-the-racetrack Rolex, Cosmograph Daytona history]
+<span id="day-date-family"></span>
+== Day-Date ==
+Day-Date calibers form their own family. Four-digit references set both calendar displays through the hands; five-digit references introduced quickset.
+<span id="cal-1055"></span>
+=== Cal. 1055 ===
+[[File:Cal 1055 movement.webp|thumb|right|220px|Cal. 1055, period parts-catalogue illustration, front and back|alt=Cal. 1055, period parts-catalogue illustration, front and back]]
+{| class="wikitable" style="width:280px; font-size:90%;"
+! detail
+! value
+|-
+| type
+| Automatic
+|-
+| jewels
+| 25
+|-
+| frequency
+| 18,000 vph (2.5 Hz)
+|-
+| power reserve
+| 42h
+|-
+| escapement
+| Straight-line lever
+|-
+| balance
+| Monometallic
+|-
+| shock
+| KIF
+|}
+Cal. 1055 is documented in the first four-digit Day-Date references, from 1956 to 1959: refs. 6510, 6511, 6611, 6612 and 6613. Its rhodium-plated bridges carry oeil-de-perdrix ("partridge-eye") circular graining rather than Côtes de Genève. Documented examples were adjusted to temperature and five positions.
+Reference histories commonly date the 6611 to 1957 and associate it with the second, chronometer-certified 1055 generation. Phillips lists caliber 1055 on its 1956 gold 6611 and 1055B on its 1958 white-gold 6611B; catalogues do not use the suffix consistently. The dial wording changes to “Superlative Chronometer Officially Certified.”
+catalogues such as [https://www.phillips.com/detail/rolex/CH080115/43 Phillips lot 43], [https://www.bonhams.com/auction/20747/lot/353/ Bonhams lot 353], and [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend lot 67] show the same naming problem: Phillips (1958 platinum case 403,680), Bonhams (circa-1959 gold 6612/8), and Monaco Legend (1958 6612B examples) list Cal. 1055, while [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie’s Dubai lot 65] uses B1055 and other catalogues use 1055B. Keep the calibre label attached to the specific watch and source; those descriptions do not establish that every 6612 retained its original movement.
+For examples catalogued as 6612B, Monaco Legend lists Cal. 1055 on yellow-gold case 384,933, white-gold case 394,866 and platinum case 403,679. Phillips lists B1055 on platinum case 446,052; Christie's Dubai uses B1055 while listing the case as 446,062. Treat these as lot-specific catalogue labels. The Dubai case number conflicts with Phillips and Sotheby's, which both give 446,052. [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-182 Monaco Legend, lot 182]; [https://www.monacolegendauctions.com/index.php/auction/exclusive-timepieces-36/lot-26 Monaco Legend, lot 26]; [https://www.monacolegendauctions.com/auction/exclusive-timepieces-38/lot-67 Monaco Legend, lot 67]; [https://www.phillips.com/detail/rolex/151223 Phillips, lot 155]; [https://onlineonly.christies.com/s/watches-online-dubai-edit/rolex-day-date-ref-6612b-extremely-rare-attractive-platinum-diamond-65/195872 Christie's Dubai, lot 65].
+The arrival of the free-sprung Microstella balance is disputed. The usual account places it with the 66xx revision, but an auction description identifies a first-generation 6511 as free-sprung. Neither generation has quickset or hacking.
+Steel school-watch records create a separate problem: Antiquorum lists 1556 for a 2002 lot and 1066 for a 2013 lot, while Phillips describes later steel Day-Date prototypes with 1555-series movements. These are catalogue descriptions of disputed school/prototype watches, not confirmed 6611 production fitments. See [[Reference:6611|the 6611 record]] for the lot-level distinctions.
+Auction catalogues also disagree on the movement fitted to ref. 6511. Phillips lists Cal. 1555 for case 111,654; Phillips lot 41, Antiquorum lot 81, Bonhams lot 156, and Monaco Legend lots 22 and 220 list Cal. 1055. The lot descriptions do not establish whether the 1555 label is a mistake or a later movement. Keep the attribution attached to the individual lot.
 <span id="cal-1555"></span>
 === Cal. 1555 ===
@@ Line 2,488: / Line 2,689: @@
 |}
-Cal. 3055 powered the refs. 18038, 18048, 18078 and early 18238 from 1977 to 1988. It introduced quickset for the date, while the day still advanced through the motion of the hands. The balance cock provides the usual visual distinction from Cal. 3155, which uses a full transversal bridge. Common references give a height of 6.3mm, but Rolex's parts diagram specifies 7.11mm.
+Cal. 3055 powered refs. 18038, 18039, 18048, 18049, 18078, 18079 and early 18238 in the 1977–1988 generation. It introduced quickset for the date, while the day still advanced through the motion of the hands. The balance cock provides the usual visual distinction from Cal. 3155, which uses a full transversal bridge. Common references give a height of 6.3mm, but Rolex's parts diagram specifies 7.11mm.
 <span id="cal-3155"></span>
@@ Line 2,659: / Line 2,860: @@
 == Related but not Rolex ==
-Gruen Cal. 877 and the Bubbleback-era "9¾ ligne" description are often misidentified as Rolex calibers. Gruen's Cal. 877, used in the Techni-Quadron, is an Aegler-built architectural sibling of Cal. 300 sold under Gruen's name in the United States. It was never a Rolex commercial number. A Bubbleback-era "9¾ ligne" description records only the movement's size class, not a distinct caliber designation.
+Gruen Cal. 877 and the Bubbleback-era "9¾ ligne" description are often misidentified as Rolex calibers. Gruen's Cal. 877, used in the Techni-Quadron, is an Aegler-built architectural sibling of Cal. 300 sold under Gruen's name in the United States. It was never a Rolex commercial number. A Bubbleback-era "9¾ ligne" description records only the movement's size class, not a distinct caliber designation. The three circa-1940 Christie’s ref. 3064 catalogues reviewed for this audit use the same size-class wording and do not name a caliber; keep the 3064 movement attribution tied to those lot descriptions.
-+== Sources by caliber ==
+== Sources ==
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-63 Antiquorum, ref. 6567, 1956, Cal. 1030]
+* [https://www.adams.ie/W103-lot-33-ROLEX-REF-1022-OYSTER-PERPETUAL-18K-YELLOW-GOLD-FLORENTINE-FINISH-CASE-A?auction_no=W103&page_no=3&sort_by=lot_no Adams, ref. 1022, 2025, Cal. 1560]
+* [https://images3.bonhams.com/original?src=Images%2Flive%2F2015-04%2F23%2FS-22886-0-1.pdf Bonhams, ref. 1022, 2015, Cal. 1560]
+* [https://www.pandolfini.it/it/asta-0036-1/orologio-da-rolex-oyster-perpetual-ref-1022--201405270143200 Pandolfini, ref. 1022, 2014, Cal. 1560]
+* [https://www.tajan.com/auction-lot/rolex-oyster-perpetual-ref-1022-vers-1964-montre-_FA27968B44 Tajan, ref. 1022, 2014, automatic movement; caliber not stated]
+* [https://shop.hodinkee.com/products/1963-rolex-oyster-perpetual-ref-1022-florentine-finish HODINKEE Shop, ref. 1022, 1963, Cal. 1560]
+* [https://www.sothebys.com/en/buy/auction/2023/important-watches-online/prince-imperial-reference-1645-a-rolesium-steel Sotheby’s, 2023, Prince Imperial 1645, lot 331]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-1645-prince-imperial-lot-357-321 Antiquorum, 2022, Prince Imperial 1645, lot 321]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-113-16 Antiquorum, 2006, Prince Imperial 1645, lot 16]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-1645-lot-320-31 Antiquorum, 2019, Prince Imperial 1645, lot 31]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-266-70 Antiquorum, 2012, Prince Imperial 1645, lot 70]
-The map below links each movement entry with the registry sources used for its summary fields. A link supports the section as a whole; disputed fields remain qualified in the prose. Calibers without an entity record remain covered by the general source list below.
-{| class="wikitable sortable"
-! Caliber !! Registry sources
-|}
 * [https://www.phillips.com/detail/rolex/CH080115/40 Phillips, 2015, ref. 6511 case 111,654, movement listed as 1555]
 * [https://www.phillips.com/detail/rolex/CH080115/41 Phillips, 2015, ref. 6511 case 134,692, movement listed as 1055]
-== Sources ==
 * [https://www.phillips.com/detail/rolex/CH080115/50 Phillips, 2015, 6611 case 214,124, caliber 1055]
 * [https://www.phillips.com/detail/rolex/CH080515/154 Phillips, 2015, 6611B case 401,546, caliber 1055B]
@@ Line 2,726: / Line 2,931: @@
 * [https://www.emmywatch.com EmmyWatch — vintage restoration movement photography]
 * [https://monochrome-watches.com/complete-history-of-the-rolex-milgauss/ Monochrome — Complete History of the Rolex Milgauss]
+* [https://www.christies.com/en/lot/lot-6067487 Christie’s, ref. 6543 case 145'111, Cal. 1080]
+* [https://www.christies.com/lot/lot-5612347 Christie’s, ref. 6543 case 145'159, Cal. 1065]
+* [https://revolutionwatch.com/rolex-milgauss-one-in-a-thousand/ Revolution, Milgauss movement and 6543 history]
+* [https://www.sothebys.com/en/auctions/ecatalogue/2018/important-watches-n09952/lot.256.html Sotheby’s, 6541 case 412'479, Cal. 1080]
+* [https://www.phillips.com/detail/rolex/206388 Phillips, same case and movement number, Cal. 1055]
 * [https://www.robbreport.com/style/watch-collector/most-expensive-rolex-watches-ever-sold-at-auction/ Robb Report — The Most Expensive Rolex Watches Ever Sold at Auction] (Sotheby's Mercedes Gleitze Oyster, November 2025)
 * [https://catalog.antiquorum.swiss Antiquorum — auction lot catalogue]
@@ Line 2,749: / Line 2,959: @@
 * [https://www.phillips.com/detail/rolex/CH080515/284 Phillips Geneva, 2015, ref. 6075 case 714440]: catalogued as A.296, 18 jewels.
 * [https://www.christies.com/en/lot/lot-6042730 Christie’s, ref. 6075 case 699455]: catalogued as A.295.
+* [https://live.mortonsubastas.com/en/online-auctions/morton-subastas/reloj-rolex-vintage-oyster-perpetual-en-acero-y-chapa-ref-1024-ca-1965---1966-movimiento-autom-tico-6579392 Morton Subastas, ref. 1024, 2024, Cal. 1560]
+* [https://www.waddingtons.ca/auction/wrist-pocket-watches-dec-12-2024/gallery/lot/5/ Waddington's, ref. 1024, 2024, Cal. 1560]
+* [https://www.dorotheum.com/de/l/5280014/ Dorotheum, ref. 1024, 2018, Cal. 1570]
+* [https://www.phillips.com/detail/rolex/HK080121/904 Phillips, ref. 1024, 2021, Cal. 1570]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-22 Antiquorum, ref. 1010/1011, 1960, Cal. 1560, case 576171]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-213-465 Antiquorum, ref. 1010/1011, 1962, Cal. 1560, case 933961]
+* [https://jewelry.ha.com/itm/timepieces/wristwatch/rolex-ref-1010-vintage-gold-oyster-perpetual-original-box-and-papers-circa-1962/a/5049-60215.s Heritage Auctions, ref. 1010, circa 1962, Cal. 1560, case 646320]
+* [https://images3.bonhams.com/original?src=Images%2Flive%2F2015-04%2F23%2FS-22886-0-1.pdf Bonhams, ref. 1010, circa 1967, Cal. 1560, case 1659430]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-1010-oyster-perpetual-lot-334-19 Antiquorum, ref. 1010, circa 1968, Cal. 1570, case 1,960,000]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-108-45 Antiquorum, ref. 1011, 1960, Cal. 1560, case 546423]
+* [https://www.christies.com/lot/lot-5496491 Christie’s, ref. 1011 case 692498, circa 1962, Cal. 1570]
+* [https://jewelry.ha.com/itm/timepieces/wristwatch/rolex-ref-1011-bombe-lugs-14k-gold-oyster-perpetual/a/171226-74030.s Heritage, ref. 1011, Cal. 1560, 2012]
+* [https://www.waddingtons.ca/?p=54274 Waddington’s, ref. 1011, Eaton’s presentation dial, Cal. 1520]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-203-530 Antiquorum, ref. 6094/6294, 2008, lot 530]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-lot-242-134 Antiquorum, ref. 6094, 2010, lot 134]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-tropical-lot-262-291 Antiquorum, ref. 6094, 2012, lot 291]
+* [https://catalog.antiquorum.swiss/en/lots/rolex-ref-6094-oysterdate-precision-lot-313-138 Antiquorum, ref. 6094, 2018, lot 138]