GMT - Technical information
White gold caseMechanical hand-wound movement, Calibre GF05
2nd time zone GMT display Tourbillon 24 Secondes rotating globe with universal time display 24 time zone worldtime display summer time indicator worldtime disc with summer time zones day-and-night indicator power-reserve indicator hour and minute display small second indicator GMT pusher equatorial sapphire crystal lateral window.
2 patents pending
Movement with patented tourbillon
Movement dimensions Diameter: 36.40 mm
Thickness: 12.46 mm
Number of parts Complete movement: 436 parts
Tourbillon cage: 87 parts
Weight of the cage: 0.36 g
Number of jewels 50
Olived-domed jewels in gold chatons
Power reserve: 72 hours
BarrelsTwo coaxial 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 wheelFree sprung variable-inertia balance with gold meantime screws (10 mm diameter)
Frequency: 21600 vibrations/hour
Balance spring Phillips terminal curve
Geneva-style stud
Main PlatesNickel silver, frosted and spotted with polished bevelling and countersinks, straight-grained flanks, nickel palladium-finish
Bridges Nickel silver, frosted and spotted, nickel-palladium finish, hand-bevelled, straight-grained flanks, polished countersinks
Gold nameplates bearing the individual number of the timepiece
Flat black polished steel tourbillon bridge, hand-bevelled
Gearing Involute circle profile
Conical gearing with corrected profiles
Tourbillon cage Inclined at a 25° angle, 24-second rotation
Cage pillars in Avional
Titanium cage bridges
Gold counterweight
Displays Hour and minute
Small second
72-hour power reserve on a sector
2nd time zone GMT indicator
24 time zone worldtime display
Rotating globe with universal time display
Summer time indicator
Day-and-night indicator
Exterior
Case White gold with asymmetrical convex sapphire crystal
Transparent back with asymmetrical convex sapphire crystal
Three-dimensional, variable geometry-shaped lugs
Polished bezel and centre band with hand-finished straight graining
Lateral window with shaped sapphire crystal
White gold pusher with raised polished engraving GMT on a hand-punched background
Raised polished engraving Greubel Forsey on a hand-punched background
Hand-engraved individual number
Gold security screws
Case dimensions Diameter: 43.50 mm
Thickness: 16.14 mm
Water resistance of the case
Water-resistant 3 atm - 30 m - 100 ft (standard NIHS 92-20/SN ISO 22810:2010)
CrownIn white gold with engraved and black lacquered GF logo
Dial Principal hour-minute dial in gold, frosted, anthracite fi nish (NAC). Hour indicator: white gold, circular graining.
Gold power reserve sector, matt lapped
Gold small second indicator, matt lapped
Gold GMT indicator, matt lapped
Applied gold Greubel Forsey logo
Hands Hour and minute in polished gold, with Super- Luminova
Small second and power-reserve in blued steel
2nd time zone GMT indicator, red triangle Strap and clasp
Hand-sewn blue or black alligator
White gold folding clasp, hand-engraved with the Greubel Forsey logo
More Details: http://novelty.greubelforsey.com/default.html