Grand Seiko
Grand Seiko Spring Drive 42 mm Mother-of-pearl 18k
Photography on request
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.
Grand Seiko · Spring Drive
Grand Seiko Spring Drive 42 mm Mother-of-pearl 18k
Reference 17815OR.93
Reference at a glance
- Brand
- Grand Seiko
- Collection
- Spring Drive
- Model
- Grand Seiko Spring Drive 42 mm Mother-of-pearl 18k
- Reference number
- 17815OR.93
- Year / era
- 1968 · 1960s — pre-quartz mechanical era
- Complication
- Flyback chronograph
- Movement
- Spring Drive
- Case material
- 18k white gold
- Dial type
- Mother-of-pearl
- Strap / bracelet
- Jubilee bracelet
- Water resistance
- 50 m
- Limited-edition status
- Regular production, not a limited edition
Case, dial & bracelet
- Case dimensions
- 42 mm
- Case thickness
- 8.8 mm
- Case material
- 18k white gold
- Bezel
- Baguette diamond rainbow
- Crystal
- Sapphire with internal AR treatment
- Dial
- Mother-of-pearl
- Hands
- Blued steel Breguet-style hands
- Indexes
- Diamond-set hour markers
- Bracelet / strap
- Jubilee bracelet
- Clasp / buckle
- Pin buckle in matching case metal
- Water resistance
- 50 m
Movement
- Movement / calibre
- Calibre 85F — Spring Drive
- Movement type
- Automatic with micro-rotor
- Frequency
- 28,800 vph (4 Hz)
- Power reserve
- 72 hours
- Number of jewels
- 21 jewels
- Complications
- Flyback chronograph
- Functions
- Hours, minutes, small seconds
- Watchmaker
- Assembled and regulated by a single watchmaker, who signs off the piece before casing.
Production & market
- Production period
- 1968 – 1976
- Limited-edition quantity
- Not applicable
- Current market information
- Trades close to retail on the secondary market, with steady demand for full-set examples.
Designer
Jörg Hysek
Jörg Hysek left Rolex and Seiko's European studios to build a design practice in Geneva, giving houses such as Vacheron Constantin, Breguet, Seiko and TAG Heuer their sculptural, architecture-led cases before founding his own brand, HD3.
Historical significance
Grand Seiko Spring Drive 42 mm Mother-of-pearl 18k sits within Grand Seiko's Spring Drive line, introduced in 1968. It carries the house codes established since 1960 — 18k white gold case, mother-of-pearl dial and spring drive — and is one of the references collectors use to date the evolution of the collection.
Interesting facts
- The reference was originally planned as a one-year run and stayed in the catalogue for well over a decade.
- The case is finished by hand, alternating polished and satin-brushed surfaces in a single pass so the edges stay razor sharp.
- The movement's bridges are decorated even where they will never be seen once the watch is cased.
The House
Grand Seiko
Brand facts
- Founding year
- 1960
- Founder
- Seiko / Daini & Suwa Seikosha
- Headquarters
- Japan
- Tier
- Premium
- Major collections
- Heritage, Evolution 9, Elegance, Sport, Masterpiece, Spring Drive
- Signature technologies
- Proprietary case-hardening and polishing · Certified chronometer regulation
- Famous movements
- High-beat automatic · Spring Drive · Automatic, Swiss lever escapement · Automatic chronograph
- Notable watches
- Grand Seiko Heritage 37 mm Ice Platinum (1960) · Grand Seiko Heritage 42 mm Black Stainless (1963) · Grand Seiko Heritage 37 mm Slate Ceramic (1969) · Grand Seiko Heritage 44 mm Skeletonised Ceramic (1975)
Brand history
Grand Seiko has spent more than 66 years refining a single idea: a watch should outlive its owner. From the earliest workshop pieces to today's Heritage, the house has balanced technical ambition with a recognisable design language, and its collections remain among the most closely followed by collectors worldwide.
Seiko / Daini & Suwa Seikosha established Grand Seiko in 1960, working from Japan at a time when precision was measured by hand. The founder's obsession with finishing and accuracy still defines every Grand Seiko calibre produced today.
Historical milestones
1960
Seiko / Daini & Suwa Seikosha founds Grand Seiko in Japan.
1969
The quartz era forces Grand Seiko to redefine mechanical watchmaking.
1990
Grand Seiko enters the modern collector market with its signature lines.
2024
Grand Seiko continues to produce Heritage, Evolution 9, Elegance and other icons in limited numbers.