This week Glashutte watchmaker Moritz Grossmann debuted their first GMT watch. Available in a 41 mm x 11.85 mm white or rose gold case the Atum GMT features the primary time in the center of the dial and a peripheral 24-hour scale with an arrow indicating a second time zone, as well as if it’s day or night (in the time zone you set it to).

Adjustment of the second time zone is controlled by a dedicated crown at 10’clock and is done so it one-hour increments, forward or backward, with no effect on the 12-hour display in the center. A ratchet wheel with ratchet spring is used to adjust the time in the pre-defined hourly gearshifts.

Moritz Grossmann GMT rose gold

The 24-hour time zone ring is regulated via a complex system of gear wheels and always runs in sync with the center time. The 24-hour display follows the 12-hour hand when the center time is set using the crown.

If you’re wondering what the button located on the caseband at 4 o’clock is, here is the description directly from the watchmaker, “On average, a manually wound watch is reset weekly. It was a challenge for the watchmakers at Grossmann to improve the functional reliability and convenience of this operation. When the user briefly pulls the winding crown out, this mechanism switches to the hand-setting mode and stops the movement. The crown immediately returns to its home position but can be turned to precisely set the hands. Afterward, the movement is restarted with the pusher adjacent to the winding crown without altering the positions of the hands. At the same time, the mechanism switches back to the winding mode. This ingenious hand-setting mechanism eliminates two possible error sources: the ingress of particles into the case while the hands are being set and the unintentional alteration of the hand positions while the crown is being pushed home again.”

The hand wound movement is beautifully finished and features a German silver mainplate and bridge. Moritz Grossman caliber 100.8 measures 36.4 x 5.55 mm and beats at 3Hz with a 42-hour power reserve. Functions include hours, minutes, small seconds, 24-hour GMT.

The movement gorgeous and you can see this one through the sapphire caseback. It has a two-thirds bridge with raised gold chatons, beveled edges, a Grossmann ratchet, a cantilevered balance cock with a micrometer screw, as well as the large free sprung balance wheel.

Moritz Grossmann Atum GMT caliber 100.8

There are two white gold models, one with an argenté (silver) dial and the other in champagne, and a rose gold version with an argenté (silver) dial.

The company’s unique lance-shaped hands (reminiscent of Laurent Ferrier hands) have been handcrafted in Glashutte and are fully polished, complemented by matching polished applied hours markers which look stunning against the sunburst pattern dial, and that hint at the level of detail you can expect to see on the movement beating underneath.

Retail is approximately $33,500. Learn more at Moritz Grossmann.

Moritz Grossmann GMT

Posted by:Jason Pitsch

Jason is the founder of Professional Watches and specializes in writing, product photography, and digital marketing.