Refined precision



Christine Hutter established Grossmann Uhren in Glashütte — a town in the German state of Saxony — in November 2008. The manufactory produces precise timepieces to the very highest standards of skill with classic yet contemporary design. The TOURBILLON Brown boasts a number of unique features which demonstrate the best of Moritz Grossmann’s famed craftsmanship.

As part of Mortiz Grossmann’s 10th anniversary collection, this one-off piece has a dark brown dial which blends seamlessly with the strap. At the heart of the TOURBILLON Brown is an optimised calibre 103.0 movement, hallmarked by a flying three-minute tourbillon with a screw-secured driving wheel and a V-shaped cage, an asymmetric-arm lever escapement with a counterweight and lever banking pin, and the characteristic Grossmann balance with a suspended balance spring and regulation via poising screws in the balance-wheel rim.

The dark, chocolate brown dial exudes precision reminiscent of an aircraft cockpit. Two subsidiary dials display the seconds and hours directly and exactly. In the lower quarter, where the 6 o’clock mark usually appears, the tourbillon aperture impinges on the time span from 25 to 35 minutes. During this ten-minute segment, an extension of the minute hand sweeps a scale opposite, allowing the time to be read precisely in an original, aesthetically appealing fashion.

The timepiece uses Grossmann’s manual winding with a pusher. When the crown is pulled out to set the watch, it immediately returns to its home position. The movement is stopped and the crown can now be turned to set the hands instead of winding the watch. The stop mechanism is triggered at the same time. The stop-seconds function can operate at any time thanks to an elaborate cage design with just two triangular posts. To halt the balance, the stop device moves past the cage’s triangular frame posts when the post is aligned with the stop lever. It does this with the aid of an elastic brush made from human hair, which provides a gentle solution for the stop mechanism which also offers long-term reliability. Pressing the pusher restarts the watch.

The Moritz Grossmann brand manufactures timepieces to the highest standard of craftsmanship. Under the motto “Schönstes deutsches Handwerk”, traditional precision mechanics are combined with state-of-the-art construction and finishing technologies.

The calibre 103.0

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Tech Specs


Manufacture calibre 103.0, manually wound, adjusted in five positions

Functions / features

Flying three-minute tourbillon with screw-secured driving wheel and V-shaped balance bridge (design patent pending); Sweep minutes, off-center hours and seconds with stop seconds; replacement of the missing minute scale segment from 25 to 35 minutes with a separate scale swept by the extension of the minute hand on the opposite side (patented); Stop seconds at the balance wheel rim with a pivoting fine-hair brush (patent pending); asymmetric-arm lever escapement with counterweight and lever banking pin; Grossmann balance with suspended balance spring, adjustable with poising screws in the rim; newly developed mainspring barrel jewel bearing; brake ring on the fourth-wheel arbor made of very hard, oily guaiacum; ARCAP train wheels; Grossmann winder with pusher to deactivate the hand setting mode and start the movement; modified Glashütte stopwork with backlash; pillar movement with 2/3 plate and frame pillars in untreated German silver; hand-engraved 2/3 plate and tourbillon cock; broad horizontal Glashütte ribbing; 3-band snailing on the ratchet wheel; raised gold chatons with pan-head screws; white sapphire bearing jewels; separately removable clutch winding mechanism

No. of parts

245 (wheel train 186, cage 59)

No. of jewels

30, 4 of which in screwed gold chatons (wheel train 17, cage 13)


Lever escapement


Grossmann three-minute tourbillon with stop seconds; shock-absorbed Grossmann balance with 4 inertia and 2 poising screws, suspended Nivarox 1 balance spring with No. 80 terminal curve, Gerstenberger geometry

Cage diameter

16,0 mm

Cage speed

1 revolution in three minutes, anti-clockwise when viewed from dial side

Balance diameter

14.2 mm, frequency 18,000 semi-oscillations per hour

Power reserve

72 hours when fully wound

Operating elements

Crown in 750/000 white gold to wind the watch and set the time, pusher in 750/000 white gold to start the movement

Case dimensions

Diameter: 44.5 mm, height: 13.8 mm

Movement dimensions

Diameter: 38.4 mm, height: 7.1 mm


Three-part, in 750/000 white gold


Solid silver, three-part, brown with Arabic numerals


Manually crafted, steel or stainless steel polished

Crystal / display back

Sapphire crystal, antireflective coating on one side


Hand-stitched alligator strap with butterfly clasp in white gold

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