Greubel Forsey Nano Foudroyante EWT

Quick specs Greubel Forsey Nano Foudroyante EWT
Price: approx. $ 536,000 | approx. € 495.000 | approx. £ 415,000 | CHF 465’000
Size: 37.9 mm
Reference: not provided – limited to 11 pieces

Greubel Forsey’s latest masterpiece, the Nano Foudroyante EWT, marks its 10^th Fundamental Invention, as they call it, celebrating its 20^th anniversary. This limited-edition timepiece, restricted to just 11 pieces, represents an approach to energy management and mechanical miniaturization. It is “Experimental Watch Technology”, thus EWT, here with foudroyante seconds, a tourbillon, and a chronograph.

Greubel Forsey introduced its initial Fundamental Invention in 2004, aiming to rethink horology entirely. The Nano Foudroyante is no exception, operating on a nanojoule scale, which significantly cuts down the energy requirement per jump to just 16 nanojoules, compared to the traditional foudroyante’s 30 microjoules. This leap enables a 90% reduction in component volume, showcasing Greubel Forsey’s commitment to functional, miniature mechanisms that don’t sacrifice performance. If this sounds a bit too technical, let’s see if we can make it a bit less complicated.

What is a foudroyante?

In watchmaking, “foudroyante” (from the French word for “striking” or “lightning”) refers to a complication where a secondary hand makes rapid movements to display fractions of a second. Often found on chronograph watches, this complication provides a more precise reading of elapsed time, usually with a hand that spins around a dedicated sub dial, completing a full rotation within one second. Each tick of the hand represents fractions, commonly in increments like 1/6^th, 1/8^th, or 1/10^th of a second, depending on the watch’s movement.

With this Greubel Forsey Nano Foudroyante EWT it is 1/6^th of a second. The foudroyante feature is especially admired in high-precision watches, as it requires a movement capable of high frequency, often beyond the standard 28,800 vibrations per hour (vph). However, GF’s movement runs with 21,600 vibrations per hour, at 3 Hertz. Even more highly technical, demonstrating the movement’s capacity to measure and display time with impressive accuracy.

Nanoscale tolerances

We try to speak the normal language here, as explaining the technical complexity becomes harder now. The beating of a watch costs energy, That is why it runs on a wounded spring that slowly unwinds. Or a battery when it’s a quartz. Now, the more complicated the watch, with lots of gears and other moving parts, the more energy it uses.

Therefore, extremely detailed and difficult complications need a lot of energy. And space too, unless you can make small parts that are extremely precise. Which is mechanical miniaturization. With this Greubel Forsey Nano Foudroyante EWT it comes down to extremely precise parts that consume as little energy as possible.

Compact case with tantalum

It all leads to a compact white gold case measuring 37.9 millimeters in diameter and 10.49 millimeters in height. The bezel and back are from tantalum (Ta), a very hard, highly corrosion-resistant metal with a blue-grey color. A watch like the F.P. Journe Chronomètre Bleu Furtif for Only Watch 2023 even has a case of it. It’s a very scarce material too.

The dial’s multi-level layout in rhodium-colored gold engraved with a black lacquered hour ring and minute circle with a visual opening for the tourbillon. The layout includes distinct areas for the small seconds and a chronograph minute counter. While a frosted, engraved fraction-of-seconds display aligns with the one-minute flying tourbillon. Despite its technical nature, this dial remains uncluttered and oriented toward 12 o’clock for clear readability.

The power reserve of the Greubel Forsey Nano Foudroyante EWT is 24 hours

The watch incorporates Greubel Forsey’s flying tourbillon, with an embedded Nano Foudroyante mechanism and a platinum counterweight. It also bears a flyback column-wheel chronograph. The movement of the Nano Foudroyante EWT is a hand-wound flyback with a full day of power with the chronograph engaged.

Visible through the transparent case back, the movement’s column-wheel design and three-dimensional architecture showcase Greubel Forsey’s hallmark finish. The back also includes relief engravings on a hand-hammered background, adding a further layer of visual craftsmanship. Each tourbillon component is expertly treated with straight-graining, and polished bevels accentuate the mechanical depth of this timepiece.

Price of the Nano Foudroyante EWT

For the strap, Greubel Forsey chose a non-animal hand-sewn strap with a white gold pin buckle engraved with the GF logo.

The model is limited and has highly complicated techniques and unique features so the price, which is on request, will be hefty. The Greubel Forsey Grande Sonnerie is in the back of our heads. Costing more than a million, although it took 11 years to develop and has almost double the parts. This Nano Foudroyante EWT will not reach that price level, but let’s say half of it?

Update: the price has been revealed at 465,000 Swiss francs. Nearly half a million in euros, over half a million in US dollars.