Zitat Rolex:

"At BASELWORLD 2013, Rolex is introducing a new version of the Oyster Perpetual GMT-MASTER II in 904L steel, with a rotatable bezel featuring for the first time a two-colour ceramic CERACHROM bezel insert in blue and black representing day and night.
EXCLUSIVE TWO-COLOUR CERACHROM BEZEL
A technological and aesthetic feat, the new CERACHROM bezel insert is obtained by a unique process developed and patented by Rolex which allows this ceramic component with two distinct colours to be produced as a single piece. It echoes the traditional two-colour bezel of the original GMT-MASTER and GMT-MASTER II models. The CERACHROM insert, introduced in 2005, has the advantage of being virtually scratchproof, highly corrosion resistant, and its colour is unaffected by ultraviolet rays. Its diamond-polished surface presents an exceptional lustre. The engraved 24-hour graduations are coated with a thin layer of platinum via a PVD (Physical Vapour Deposition) process."

Das Verfahren läßt ja hoffen, dass dann noch mehr kommt in den nächsten Jahren.