Pre-SIHH 2015, Greubel Forsey is pleased to announce the launch of the GMT Black exploring a new design with a titanium case and treated with vacuum deposited ADLC. This is a unique edition of 22 pieces worldwide. The timepiece features a case measuring 43.5 mm in diameter housing a GF05 in-house movement with 24 second tourbillon inclined at a 25 degree angle, GMT function, three-dimensional globe for day/night indication, rotating disc with 24 different time zones, daylight savings indication, and 72 hour power reserve. This watch is the exact same watch as its predecessors in platinum, rose gold or white gold GMTs reviewed here but with a DLC Titanium case. The 25° inclined Tourbillon '24 Secondes' cage at 5 o'clock is one of Greubel Forsey’s major patented inventions. The single inclined tourbillon cage undergoes rapidly changing positions with a high angular velocity, thus minimizing the effects of gravity on the regulating organ and maximizing timekeeping accuracy. 

Now, let's talk about the back of the watch. As fascinating as the front, the back features a worldtimer disc with 24 cities that eases the setting of the globe and also provides the traditional worldtimer way of reading time in multiple timezones. As the cities disc rotates, so does the terrestrial globe to perfectly show night and day areas of the earth. The disc is also fitted with a central indicator for Summer Time a.k.a. Daylight Savings Time. Those cities not using DST are on a dark background and time is read on the outer chapter ring. The disc is made of sapphire crystal and the cities are in black and white. Additionally, the back also features a golden gear with a beautiful windrose serving as a useful visual reference for midday. The beating heart inside this watch is the manual wound calibre GF05 decorated with DLC frosted bridges and plates, blued screws and a small opening where the efficient spherical differential can be admired. This calibre is composed of 443 parts, 50 jewels and two co-axial series-coupled fast rotating barrels. 

This is another exemplary timepiece of the atelier’s refusal to compromise quality, inventive boldness both aesthetically and technically, and their constant pursuit to outdo themselves and achieve the highest level in timekeeping precision. The globe alone took Greubel Forsey 18 months to develop in order to achieve the visual effect desired, while the movement took years of research and development.

Sticker Price $565,000 USD. For more info on Greubel Forsey click here.