The name TEFNUT has its origins in ancient Egyptian mythology. Tefnut is an Egyptian goddess and the first offspring of Atum, the deity of creation. She symbolises the temperament of fire and the subtle elegance of the Nubian feline.
The TEFNUT model is a men’s watch that reflects a decidedly reduced form vocabulary and straightforward development process. Its personality eliminates all doubt that horological class is also a question of appearance. Exquisitely cambered gold hour markers, convex numerals at the 6 and 12 o’clock positions, two manually crafted hands conceived explicitly for this watch family, and a slender gold case are defining elements of this timepiece.
The case of the TEFNUT is crafted from noble rose or white gold. Given the extra-flat design of the movement, the silhouette of the case is exceptionally svelte as well. Thus, the watch gently hugs the wrist. Its sleek elegance is underscored by the fluted crown, four gracefully tapered lugs, and a hand-stitched alligator leather strap. The slightly cambered sapphire-crystal glass and caseback merge seamlessly with the minimal-art front and back of the TEFNUT. They protect the filigreed components and provide an unobstructed view of the individual details of the watch.
Subtle elegance meets premeditated innovation – in the TEFNUT, this philosophy is self-evident in the clearly structured, two-part solid-silver dial and in its interaction with the hands that were created especially for this model. The face pairs modern form with classic design: Slightly domed gold hour markers encircle the argenté or charcoal dial, prominently interrupted by crisp Arabic numerals in the 6 and 12 o’clock positions. Deeply carved pinstripes adorn the inner part of the charcoal dial. They grace the watch with understated momentum.
The lucid shape and the finesse of the hands of the TEFNUT are truly impressive. They are manually crafted from steel or stainless steel in numerous steps. A node that tapers toward the eye of the hand and narrows to a fine point at the tip characterises the shape that was developed especially for the TEFNUT. It assures that the time is always accurately readable.
The Calibre 102.0
The calibre 102.0 movement was newly conceived from the bottom up. With a diameter of only 26 mm and a height just under 4 mm, it is distinctly smaller and flatter than previous Moritz Grossmann movements.
The straight cut of the train bridge and the newly configured going train, the calibre looks very well organised and showcases the deliberately arranged inner life of the watch. The ARCAP alloy of the wheels contrasts well against the German-silver movement elements. The large mainspring barrel suspended between bearings on both sides is an eye-catcher as well. Despite its compact dimensions, the classic pillar movement with the main plate and the 3/5 plate features all Grossmann hallmarks such as the cantilevered balance cock with the Grossmann micrometer screw, the raised chatons, the separately removable winder module, and the mass-optimised Grossmann balance. Because of the smaller diameter of the balance, the new calibre generation breathes at a frequency of 21,600 semi-oscillations per hour and assures dependable rate stability.
- The Escapement: In the 19th century, Moritz Grossmann already realised that small pinions with 6 leaves produce very unfavourable transmission ratios. To avoid this phenomenon, he used a 16-tooth escape wheel. This concept was adopted for the escapement integrated in the calibre 102.0 movement. Due to the somewhat higher frequency of the smaller balance, it was fitted with an escape wheel that has 18 very slender, classically shaped teeth.
- The Index Adjuster: The Grossmann balance has four interchangeable inertia screws that can be used for a first-pass balance-spring matching process. Two precision poising screws make it possible to fine-tune the frequency. The balance-wheel rim features 22 equidistant bores. For material removal purposes, they can be countersunk or broached to accurately true the balance without damaging the finished rim surface. The index pointer enables the daily rate to be corrected without jeopardising the integrity of the balance. It is easily accessible once the caseback has been removed.
- The Wheel Train: Departing from the mainspring barrel, where according to Glashütte regleur Alfred Helwig the adjustment of a movement must begin, the wheel train of calibre 102.0 reflects a new concept. The barrel is bilaterally supported in jewel bearings, which reduces friction, optimises the energy balance, and improves the rate accuracy of the watch. Normally, the barrel engages with the wheel train directly at the centre wheel located at a height that lies between the barrel and the ratchet wheel. To achieve a thinner silhouette and make the best possible use of the space in the round movement available to the wheel train, the centre wheel was shifted to a different position in the TEFNUT calibre 102.0. The power produced by the mainspring barrel is now transmitted to an intermediate wheel by a single pinion and from there passed on to the repositioned centre wheel. A copper-nickel-zinc alloy called ARCAP assures the long-term brilliance of the wheels.
Manufacture calibre 102.0, manually wound, adjusted in five positions
No. of parts: 196
Jewels: 26, of which 3 in screwed gold chatons
Escapement: Lever escapement
Oscillator: Shock-resistant Grossmann balance with 4 inertia and 2 poising screws,
Nivarox 1 balance spring
Balance: Diameter: 10.0 mm, frequency: 21,600 semi-oscillations per hour
Power reserve: 48 hours when fully wound
Functions: Hours and minutes
Operating elements: Crown in 750/000 gold for winding the watch and setting the time
Case dimensions: Diameter: 39.0 mm, height: 8.5 mm
Movement dimensions: Diameter: 26.0 mm, height: 3.45 mm
Case, dial and strap
Case: Three-part, in 750/000 gold
Dial: Solid silver
Hands: Manually crafted, steel or stainless steel
Crystal and back: Sapphire crystal, antireflective coating on one side
Strap: Hand-stitched alligator strap with butterfly clasp in 750/000 gold