Greubel Forsey Nano Foudroyante in White Gold

Greubel Forsey unveils the first official limited edition of its Nano Foudroyante: a breakthrough timepiece born from years of research, now matured beyond its Experimental Watch Technology (EWT) origins. Limited to just 22 timepieces, this creation marks a significant new chapter in Greubel Forsey's 10th Fundamental Invention.

From prototype to timepiece

Originally presented in 2024 as a commemorative EWT edition, the Nano Foudroyante was Greubel Forsey’s most technically radical concept to date. Today, it has evolved into a fully realized and independent creation – no longer tethered to an anniversary or prototype designation.

The new Nano Foudroyante is crafted entirely in white gold, replacing the original combination of white gold and tantalum. It presents a different architectural identity: the gold dial is now finished in rhodium with a blue minute track, while the hands are rendered in blued steel with matching cannon pinions. The foudroyante dial itself is now white with transferred numerals, enhancing legibility and echoing the crisp visual language of the tourbillon aperture. A blue textured rubber strap completes the aesthetic – a clear evolution from the original edition, and a declaration of this timepiece’s own distinct personality.

Nanomechanics: reinventing the possible

At the heart of this timepiece lies a disruptive idea: nanomechanics – the control of energy at the nanojoule scale inside a mechanical movement. This paradigm shift enables the Nano Foudroyante to operate its eponymous complication using just 16 nanojoules per jump, compared to 30 microjoules in traditional designs – a staggering reduction by a factor of 1,800.

The complication divides each second into six segments using a lightweight, red-treated hand that rotates once per second, driven directly by the oscillations of the 3Hz balance wheel. There is no traditional gear train; instead, a minimalist series of low-inertia wheels efficiently distributes energy through the movement.

A compact and refined architecture

The Nano Foudroyante mechanism is embedded within Greubel Forsey’s first flying tourbillon, creating a visual and technical centerpiece. The foudroyante’s dial remains permanently oriented to twelve o’clock, even as the tourbillon rotates – ensuring optimal readability.

The timepiece features a hand-wound flyback with 2 patents, totaling 428 components (including 142 for the tourbillon cage). Despite this complexity, the movement measures just 31.60mm in diameter and fits within a 37.90mm white gold case – Greubel Forsey’s most compact ever.

The case is fitted with a high-domed sapphire crystal, straight-grained finishing on the caseband, and a transparent caseback. Subtle engravings – “Nano Foudroyante” and “Greubel Forsey” – stand out in polished relief over a hand-hammered background.

A new chapter, fully realised

This timepiece embodies maturity and intent, created for 22 collectors who will experience Greubel Forsey’s most energy-efficient, compact, and conceptually advanced timepiece to date.

Technical specifications

Greubel Forsey Nano Foudroyante in White Gold

Limited edition of 22 pieces

Case

• Material: White gold with high domed synthetic sapphire crystal
• Diameter: 37.90mm
• Bezel diameter: 38.30mm
• Height: 10.49mm
• Height on synthetic sapphire crystals: 14.34mm
• Hand-polished bezel, caseband with hand-finished straight-graining
• Crown with pusher, in white gold, engraved GF logo
• Pusher in white gold, hand-polished
• Transparent back with high domed synthetic sapphire crystal
• Raised polished engraving “Nano Foudroyante” and “Greubel Forsey” on a hand-punched background
• Gold security screws
• Water-resistant to 3atm - 30m - 100ft

Dial

• Multi-level in gold, rhodium-coloured, minute-circle with blue finish, small seconds and chronograph minutes counter with polished bevel, engraved and lacquered indications, with a visual opening for the tourbillon
• Foudroyante in light alloy, polished bevel with flat black polished central plate.

Hands

• Hours and minutes in polished blued steel with Super-LumiNova, hand-polished countersink, flat black polished head
• Small seconds and chronograph hands in polished blued steel, hand-polished countersink, flat black polished head
• Tourbillon and Foudroyante in light alloy, red treatment

Movement

• Hand-wound chronograph movement with 2 patents
• Flying tourbillon with Nano Foudroyante • hours and minutes • small seconds • 60-second tourbillon rotation • chronograph seconds (trotteuse) • 60-minute counter • flyback function
• Diameter: 31.60mm
• Thickness: 9.40mm
• Movement: 428 parts
• Tourbillon cage: 142 parts
• Weight of the cage: 0.835g
• Number of jewels: 53
• Olived-domed jewels in gold chatons
• Frequency: 21'600 vph (3 Hz)
• Chronometric power reserve: One full day, with chronograph engaged

Tourbillon

• Flying Tourbillon with embedded Nano Foudroyante mechanism
• Foudroyante dial, constant vertical indication
• Titanium cage bridges, polished bevelling, straight-grained flanks, with engraved GF logo
• Platinum counterweight

Functions/Indications

• Hours and minutes
• Small seconds
• 60-second tourbillon rotation
• Foudroyante, sixth of a second

Chronograph

• 60-second flange
• 60-minute counter, semi-instantaneous

Strap and buckle

• Hand-sewn textured rubber
• White gold pin buckle, hand-engraved GF logo

MSRP: CHF 465'000 (excl. taxes)

For more information, please visit greubelforsey.com