Rolex Oyster Perpetual 2240

A checked version of this page, approved on 23 August 2026, was based on this revision.

Two Antiquorum catalogues from 1995 identify ref. 2240 as a 32mm steel Oyster Perpetual with centre seconds and a self-winding, 19-jewel movement. That makes its Bubbleback classification probable. Neither catalogue shows a reference engraving, movement, or caseback, so the identity and domed-back construction have not been documented together on one watch.

Arthur Johnson & Sons attributed a domed-back Rolex to ref. 2240 twice in March 2026. Its photographs show the case profile and movement number 31706, but no case number or reference engraving. The dial reads Rolex Oyster rather than Oyster Perpetual. It is useful evidence for a Bubbleback-form watch, but not a securely identified ref. 2240.

Core facts

detail	value
reference	2240
family	Oyster Perpetual; Bubbleback classification probable, not fully documented
production	no documented range; Antiquorum dates individual examples to the 1930s and 1940s
case diameter	32mm
case shape	tonneau
case	steel tonneau, polished and satin-finished on the two Antiquorum examples; screw-down back and crown
caseback profile	not shown on the Antiquorum watches; domed on the Arthur Johnson watch attributed to ref. 2240
bezel	smooth, polished
crystal	material not stated in the catalogues
crown	screw-down
winding	self-winding
seconds	centre seconds
movement	9¾ lignes, rhodium-plated, 19 jewels, lever escapement, monometallic balance, self-compensating Breguet balance-spring. No caliber number published
case materials	stainless steel on all three attributed watches
dials documented	two Antiquorum watches wear different mat-silver layouts; the Arthur Johnson attribution has a silvered Roman sector dial; original fitment unproved
dial designations	"Oyster Perpetual, Superlative Chronometer, Officially Certified"; "Oyster Perpetual Chronomètre"; "Rolex Oyster"

Where it sits in the line

Both Antiquorum descriptions specify centre seconds, self-winding, 19 jewels and a 9¾-ligne movement. Those details place the watches among early Oyster Perpetual automatics, but they do not identify a caliber or case generation. The catalogues describe screw-down backs and crowns; neither calls the case two-piece or shows it disassembled.

References 1873 and 2765 are useful contrasts because catalogued examples are manually wound, and ref. 1873 is explicitly described with a flat back. Their similar tonneau outlines do not prove that they share case construction with ref. 2240.

Production outline

Four online auction appearances have been located, representing three watches. Antiquorum sold two different examples in 1995. Arthur Johnson listed the same watch on 7 and 14 March 2026, first with a recorded £800 hammer and then at £680. The reason for the reoffer is not published.

Antiquorum dated one watch to the 1930s and the other to the 1940s. Neither listing gives a case number, and the Arthur Johnson photographs show no case number or reference engraving. These dates remain catalogue estimates for individual watches; they do not establish a production range. All three attributed watches are steel.

Movement notes

Both Antiquorum catalogues describe the movement as self-winding, 9¾ lignes and 19 jewels, with a lever escapement, monometallic balance, Breguet balance spring and centre seconds. Automatic winding rests on the explicit catalogue descriptions, not on the size: Rolex also used 9¾-ligne manual movements.

Neither catalogue names a caliber. The centre-seconds layout makes Cal. 630 or a related 600-series Perpetual plausible, but the jewel count and hand layout are not enough to make that assignment. The Arthur Johnson movement is engraved No. 31706, but its caliber marking and the watch's reference engraving are not shown.

Dial map

Painted Arabic numerals and outer minute track, the Hong Kong lot

The three attributed watches wear different dials. The photographs document their condition at sale, not original delivery.

The Geneva example carries a mat silver dial with applied gold indexes and radium-filled bâton hands, reading Oyster Perpetual below the coronet and carrying its chronometer designation above six o'clock. The Hong Kong example is mat silver, with painted Arabic numerals at every hour, an outer minute track with five-minute markers, Chronomètre above six, and the same radium-filled bâton hands.

Applied Roman numerals on a sector-style dial signed Rolex Oyster, the Nottingham lot

The Nottingham watch has a silvered dial with a faint sector pattern, applied Roman numerals at the even hours and applied batons at the odd ones, a printed outer minute track, gilt leaf hands and a centre seconds hand. Its surface is heavily crazed. The signature reads Rolex Oyster rather than Oyster Perpetual, a warning when assessing the auctioneer's automatic ref. 2240 attribution.

The Geneva watch has visible Superlative Chronometer Officially Certified wording. Rolex dates that designation to the late 1950s, while Antiquorum dates the watch to the 1940s. At least one element of that record is therefore wrong. Without a case number and closer dial examination, the evidence cannot distinguish a later replacement or refinish from a misdated watch.

Case, bezel, crystal, and crown

Antiquorum describes both watches as 32mm steel tonneau cases, polished and satin-finished, with screw-down backs and crowns. It calls them waterproof in period catalogue language. The crystal material and internal case construction are not stated.

Domed, coin-edged screw-down back on the Arthur Johnson watch attributed to ref. 2240; no reference engraving was shown

The Arthur Johnson watch has a pronounced domed back seated in a coin-edged screw ring. Its crown would not screw down. The photographs do not show a reference engraving or case number, so this construction cannot yet be tied securely to ref. 2240.

Christie's description of a ref. 2764 shows why Antiquorum's silence is inconclusive: the house calls the 2764 a Bubbleback but does not describe its back as domed in the technical text. That comparison explains the missing word; it does not identify the 2240's case construction or caliber.

Bracelets, end links, and clasps

All three attributed watches were photographed on leather straps. No ref. 2240-specific factory bracelet or end-link documentation has been located.

Auction record

Venue	Date	Lot	Dated by catalogue	Dial	Estimate	Result
Antiquorum, Geneva (Hôtel des Bergues)	1995-04-22	304	1940s	Mat silver, applied gold indexes, bâton radium hands	CHF 2,600–2,800 (USD 2,200–2,400)	Not published
Antiquorum, Hong Kong (Hotel Furama Kempinski)	1995-06-14	29	1930s	Mat silver, painted Arabic numerals, bâton radium hands	HKD 15,000–18,000 (USD 2,000–2,200)	Not published
Arthur Johnson & Sons, Nottingham	2026-03-07	7353	Not dated	Silvered sector, applied Roman numerals, gilt leaf hands	Not published	GBP 800 hammer recorded; reoffered one week later
Arthur Johnson & Sons, Nottingham (The Saturday Auctions)	2026-03-14	7287	Not dated	Silvered sector, applied Roman numerals, gilt leaf hands	Not published	GBP 680 hammer

Neither Antiquorum page publishes a realised price. The Nottingham entries are not two examples: the photographs show the same watch, first listed as lot 7353 and reoffered one week later as lot 7287. The reason for the reoffer is unknown, so the £800 and £680 figures should not be treated as two independent market observations.

The secure record is narrower. Antiquorum catalogued two different self-winding ref. 2240 watches with 9¾-ligne, 19-jewel movements and centre seconds. Arthur Johnson catalogued one domed-back automatic watch as ref. 2240 twice, without showing the reference engraving.

Related references

Bubbleback 2764 — Cal. 620N "Super Precision"
Bubbleback 2940 — centre-seconds contemporary
Bubbleback 3131 — the 1936 two-piece case transition
Oyster Chronometer 2765 — the manual flat-back that shares the list but not the mechanics
Oyster Royal 1873 — manual flat-back Oyster