Greubel Forsey Quadruple Tourbillon Black Limited Edition

Greubel Forsey presents a black version of the brand’s second Fundamental Invention, the Quadruple Tourbillon. This new model features a light-weight titanium case coated with a black ADLC treatment.

Greubel Forsey Quadruple Tourbillon Black Limited Edition

The Greubel Forsey Quadruple Tourbillon Black version is limited to 8 pieces. The hand-wound mechanical movement incorporates the patented Quadruple tourbillon mechanism, small seconds, power-reserve indicator and centrally positioned hour and minutes.

Greubel Forsey Quadruple Tourbillon Black Limited Edition

This model features a black multilevel dial in gold. The watch comes with a black rubber or hand-sewn alligator strap with a black ADLC titanium folding clasp.

Technical details

Model: Greubel Forsey Quadruple Tourbillon Black Limited Edition

Movement specifications

Movement dimensions
Diameter: 36.40 mm
Thickness: 9.70 mm

Number of parts
Movement: 534 parts
4 tourbillon cages: 261 parts
Total weight of the cages: 2.26 g
Spherical differential: 28 parts

Number of jewels
• 63
• Olived-domed jewels in gold chatons

Chronometric power reserve
• 50 hours

Barrels
• Two series-coupled fast rotating barrels (1 turn in 3.2 hours), one of which is equipped with a slipping spring to avoid excess tension

Balance wheel
• Variable-inertia with white gold mean-time screws (10.70 mm diameter)

Frequency
• 21’600 vibrations/hour

Balance spring
• Phillips terminal curve
• Geneva-style stud

Main plates
• Nickel silver, spotted with polished bevelling and countersinks, straight-grained flanks, nickel-palladium treatment

Bridges
• Nickel silver, frosted and spotted with polished bevelling and countersinks, straight-grained flanks, nickel-palladium treatment
• Gold plate engraved with the individual number
• Two steel tourbillon bridges (movement side) : flat black polished with hand-polished bevelling and countersinks
• Two synthetic sapphire tourbillon bridges (dial side)

Inner tourbillons
• Inclined at a 30° angle, 1 rotation per minute

Outer tourbillons
• 1 rotation in 4 minutes
• Hand-bevelled and open-worked cage pillars
• 1 gold counterweight per double cage bearing the individual number of the timepiece

Gearing
• Involute circle profile
• Conical gearing with profiled teeth

Displays
Hours and minutes
Small seconds on a sector (mean performance)
50-hours power reserve on a sector
240-seconds outer-tourbillon rotation (on one of the outer cages)

Case, dial and strap

Case
Black ADLC titanium case with asymmetrical convex synthetic sapphire crystal
Transparent back with asymmetrical convex synthetic sapphire crystal
Lateral window with shaped synthetic sapphire crystal
Three-dimensional, variable geometry-shaped lugs
Raised polished engraving “Quadruple” and
“Greubel Forsey” on a hand-punched background
Gold security screws
Polished bezel, caseband with hand-finished straight graining
Engraved individual number
Case diameter: 43.50 mm
Height: 16.11 mm
Crown: In black ADLC titanium with engraved and GF logo
Water resistance: 3 atm – 30 m – 100 ft (standard NIHS 92-20/SN ISO 22810:2010)

Dial
Multi-level in gold, black colour
Gold hour markers
Gold display sectors
Gold GF logo

Hands
Hours and minutes in polished gold, with Super-LumiNova
Small seconds, 240-seconds and power-reserve in polished gold

Strap and clasp
Black rubber or hand-sewn alligator
Black ADLC titanium folding clasp, engraved with the GF logo

Edition
Limited edition of 8 pieces in black ADLC titanium