Front view
Dial, hands and bezel as delivered.
Case-back view
Case-back engraving and, where fitted, the sapphire display.
Movement
Calibre with its finishing and decoration.
On the wrist
Worn shot for proportion and strap drape.
Arnold & Son · Constant Force
Arnold & Son Constant Force 37 mm Mother-of-pearl 18k
Reference 40085OR.90
Reference at a glance
- Brand
- Arnold & Son
- Collection
- Constant Force
- Model
- Arnold & Son Constant Force 37 mm Mother-of-pearl 18k
- Reference number
- 40085OR.90
- Year / era
- 1957 · 1950s — pre-quartz mechanical era
- Complication
- Chronograph
- Movement
- In-house automatic with 22k gold rotor
- Case material
- 18k rose gold
- Dial type
- Mother-of-pearl
- Strap / bracelet
- Rubber strap with titanium clasp
- Water resistance
- 30 m
- Limited-edition status
- Limited edition of 50 pieces
Case, dial & bracelet
- Case dimensions
- 37 mm
- Case thickness
- 12.6 mm
- Case material
- 18k rose gold
- Bezel
- Bidirectional 24-hour Cerachrom
- Crystal
- Anti-reflective sapphire, double-domed
- Dial
- Mother-of-pearl
- Hands
- Rhodium-plated baton hands with luminous fill
- Indexes
- Applied Roman numerals
- Bracelet / strap
- Rubber strap with titanium clasp
- Clasp / buckle
- Pin buckle in matching case metal
- Water resistance
- 30 m
Movement
- Movement / calibre
- Calibre 14E — In-house automatic with 22k gold rotor
- Movement type
- Automatic with micro-rotor
- Frequency
- 25,200 vph (3.5 Hz)
- Power reserve
- 45 hours
- Number of jewels
- 25 jewels
- Complications
- Chronograph
- Functions
- Hours, minutes, seconds, date
- Watchmaker
- The calibre is built in-house and adjusted in five positions before delivery.
Production & market
- Production period
- 1957 – 1960
- Limited-edition quantity
- 50 pieces
- Current market information
- Trades close to retail on the secondary market, with steady demand for full-set examples.
Designer
Gérald Genta
Gérald Genta (1931–2011) trained as a goldsmith in Geneva and became the most influential watch designer of the 20th century. Working freelance, he sketched the Audemars Piguet Royal Oak overnight in 1970, followed by the Patek Philippe Nautilus, the IWC Ingenieur SL and the Bulgari Bulgari — defining the integrated-bracelet luxury sports watch as a category.
Historical significance
Arnold & Son Constant Force 37 mm Mother-of-pearl 18k sits within Arnold & Son's Constant Force line, introduced in 1957. It carries the house codes established since 1764 — 18k rose gold case, mother-of-pearl dial and in-house automatic with 22k gold rotor — and is one of the references collectors use to date the evolution of the collection.
Interesting facts
- The movement's bridges are decorated even where they will never be seen once the watch is cased.
- The bracelet tapers across its length, which is why the profile looks thinner on the wrist than the specification suggests.
- The reference was originally planned as a one-year run and stayed in the catalogue for well over a decade.
The House
Arnold & Son
Brand facts
- Founding year
- 1764
- Founder
- John Arnold
- Headquarters
- United Kingdom
- Tier
- Ultra-Luxury & Haute Horlogerie
- Major collections
- Perpetual Moon, Luna Magna, DSTB, Nebula, Globetrotter, Constant Force
- Signature technologies
- In-house hairspring production · Hand-applied guilloché dials · Proprietary case-hardening and polishing
- Famous movements
- In-house tourbillon, manual-winding · In-house manual-winding, hand-finished · In-house automatic micro-rotor · In-house automatic with 22k gold rotor
- Notable watches
- Arnold & Son Perpetual Moon 44 mm Silvered Stainless (1988) · Arnold & Son Perpetual Moon 39 mm Black Stainless (2001) · Arnold & Son Perpetual Moon 44 mm Ice Quartz (1968) · Arnold & Son Perpetual Moon 36 mm Skeletonised Carbon (1950)
Brand history
Arnold & Son has spent more than 262 years refining a single idea: a watch should outlive its owner. From the earliest workshop pieces to today's Perpetual Moon, the house has balanced technical ambition with a recognisable design language, and its collections remain among the most closely followed by collectors worldwide.
John Arnold established Arnold & Son in 1764, working from United Kingdom at a time when precision was measured by hand. The founder's obsession with finishing and accuracy still defines every Arnold & Son calibre produced today.
Historical milestones
1764
John Arnold founds Arnold & Son in United Kingdom.
1804
Arnold & Son earns its first international recognition for precision timekeeping.
1969
The quartz era forces Arnold & Son to redefine mechanical watchmaking.
1990
Arnold & Son enters the modern collector market with its signature lines.
2024
Arnold & Son continues to produce Perpetual Moon, Luna Magna, DSTB and other icons in limited numbers.
More Constant Force
Arnold & Son Constant Force 39 mm Mother-of-pearl Carbon
Ref. 62952OR.79
Arnold & Son Constant Force 42 mm Salmon 18k
Ref. 33806OR.57
Arnold & Son Constant Force 44 mm Salmon 18k
Ref. 56903OR.61
Arnold & Son Constant Force 42 mm Blue Stainless
Ref. 97877ST.12
Arnold & Son Constant Force 43 mm Salmon 18k
Ref. 91202OR.90