Rolex 5031 "Ovettone" Transitional Bubbleback
Bubbleback › 5031
The 5031 is the stainless steel and gold two-tone twin of the solid-gold ref 5030, the one-year bridge between the 1945–1949 ref 4467 and the 1949 ref 6031. Same 36mm case, same A.295 automatic movement, same straight case flanks between the lugs, same small Brevet crown carried over from the 32mm Bubblebacks. The architectural difference is the construction: a Rolesor-style steel-and-gold two-tone case rather than solid gold. Both yellow-gold and pink-gold accents are documented on the 5031's two-tone case.
Core facts
| detail | value |
|---|---|
| reference | 5031 |
| family | Datejust / Big Bubbleback / Ovettone |
| production | about 1948 (one-year window) |
| case diameter | 36mm (tonneau Oyster, Ovettone profile) |
| case construction | three-piece, screw-down caseback and crown |
| case materials | Stainless steel and 18K gold, two-tone (Rolesor-style); both yellow-gold and pink-gold accents documented |
| bezel | fine milled/reeded gold, matching the accent metal |
| crystal | acrylic, domed |
| crown | small screw-down Brevet (earliest style) |
| movement | Cal. A.295 (listed as Cal. 740 / Cal. 745 in parts catalogues) |
| date complication | yes — date at 3 o'clock, gradual creep at midnight |
| Cyclops | no (introduced on ref 6305 in 1954) |
| "Datejust" text on dial | no (first consistent appearance on ref 6105 in 1953) |
| solid-gold twin | 5030 |
| successor | 6031 |
What the 5031 is
The 5031 is the steel-and-gold two-tone twin to the solid-gold 5030: same 36mm Big Bubbleback Datejust architecture, same movement, same transitional place in the line, but built as a Rolesor-style two-tone case rather than solid gold. Documented examples carry both yellow-gold and pink-gold accents against the steel case and bracelet.
Placing the 5031 in the Ovettone sequence
The full Ovettone arc runs: 4467 (1945) → 5028 / 5030 / 5031 (1947–48) → 6030 / 6031 (1949) → 6074 / 6075 (1950) → 6105 (1953, first "Datejust" text) → 6305 (1954, first Cyclops) → 6604 / 6605 (1956–57, first instantaneous date via Cal. 1065). The 5031 sits on the transitional shelf with its solid-gold twin; the closest direct successor is the 1949 ref 6031, which reverts to the 4467's curvier case flanks after the straight-flank 5031 experiment.
Italian auction houses (Pandolfini, Aste Bolaffi) and mainstream dealer usage include the 5030/5031 pair in the Ovettone family, alongside Edmond Saran's 2022 Le Monde Edmond treatment that names the 5030 explicitly. The narrower dealer convention excludes the 50xx pair and reserves the term for 4467, 6031, 6074, and 6075. Both framings coexist in current literature.
The 36mm Big Bubbleback case — the straight-flank experiment in two-tone
Case architecture on the 5031 is identical to the 5030's shape and follows the same two one-year deviations from the 4467 and 60xx standard: the perfectly straight flanks between the lugs, and the small Brevet crown carried over from the 32mm small Bubblebacks. Three-piece Oyster construction, 36mm diameter, domed caseback housing the Perpetual rotor, fine milled/reeded bezel — but built in steel with gold accents (bezel, crown, and typically the bracelet centre links) rather than solid gold, with the accent gold documented in both yellow and pink.
The crown on the 5031 is the small screw-down Brevet in the accent gold, matching whichever color the specific example carries, cross-center, "Rolex + Oyster" marking. By the 1949 60xx generation, Rolex had switched to a larger crown that sat more naturally on the 36mm case. The 5031 is the one two-tone Big Bubbleback that still wears the old small crown; the 6031 that replaces it in 1949 wears the new one.
Case construction and configuration
The 5031 is a stainless steel and 18K gold two-tone case (Rolesor-style), documented with both yellow-gold and pink-gold accents — not a solid precious-metal case, and not restricted to one accent color. Period-correct dials match the accent metal: silvered or eggshell dials with applied gold dagger markers in the matching color, gold alpha hands with radium inserts on the lumed configurations, plain polished hands on dress configurations. Bubbleback-style coronet logos — often the "cut-off" truncated variant — and Chronometer or Certified Chronometer dial text above six on chronometer-grade examples are both documented.
Date wheels follow the broader Ovettone convention: typically black on white by the 5031 era, with roulette (alternating red/black) wheels documented on some peer examples in the same window. A 5031 with a roulette wheel is not impossible, but it is less common than on earlier 4467 examples.
A solid-gold 5031 is not documented — that construction is the separate reference 5030.
Movement: Cal. A.295
Same as the 5030 mechanically: cal. A.295 in the 740/745 family, with center seconds, date, no shock protection, and the old slow date change rather than a later snap change.
Dial feet positions are specific to the A.295 and differ from the A.296 used in ref 6105 and later. A 5031 dial on an A.296 movement is not period-correct. The Vintage Rolex Forum documentation by specialist Xeramic (thread t-274914) is the standard reference on this check.
Authentication priorities
- Movement. Cal. A.295, cross-listed as Cal. 740 or Cal. 745. A later caliber in a 5031 case is a service swap.
- Case metal. Stainless steel and 18K gold, two-tone construction — consistent accent color (yellow or pink) across crown, bezel, markers, hands, and bracelet centre links (if present). A solid-gold 5031 claim is a misidentification; that construction is the 5030.
- Crown. Small Brevet, in the accent gold matching the rest of the case. The larger crown of the 6031 and subsequent Ovettones is not correct for the 5031.
- Case flanks. Straight between the lugs; the 5030/5031 distinguishing shape feature.
- Bezel. Fine milled or reeded gold, matching the accent color, in the 4467 idiom.
- Dial. "Oyster Perpetual" with Chronometer or Certified Chronometer designation above six on chronometer-grade examples. No "Datejust" text on a period-correct 5031 dial.
- Dial feet position. Specific to A.295.
Related references
- Bubbleback 5030 — 1948
- Bubbleback 4467 — 1945–1949
- Bubbleback 6031 — 1949
- Bubbleback 3595 — 1941–1949
- Bubbleback 2940 — 1940–1949
- Bubbleback 6075 — 1950–1953
See also the Bubbleback family index, movement reference, bracelet & clasp guide, and serial numbers by year.
Sources
- The Vintage Rolex Field Manual — Colin A. White, Morning Tundra
- Le Monde Edmond — Datejust: A Closer Look at a Rolex Icon — Le Monde Edmond
- Monochrome Watches — The Evergreens: Complete History of the Rolex Datejust — Monochrome
- Robb Report — A Collector's Guide to Rolex Bubbleback Watches 1931-1950s — Robb Report
- Pandolfini Casa d'Aste catalog usage — 'Ovetto' for 32mm Bubblebacks, 'Ovettone' for 36mm Big Bubblebacks — Pandolfini Casa d'Aste, Pandolfini
- Aste Bolaffi catalog usage of 'Ovetto' for standard 32mm Bubblebacks — Aste Bolaffi