Here's how Rolex makes the ceramic bezel for the SS GMTBut how would you make one? Actually... I wonder how they make that ceramic?!
"A technological and aesthetic feat, the new Cerachrom bezel insert is obtained by a unique process developed 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 black colour is achieved via a process that consists of impregnating half the insert with a controlled quantity of a solution of chemical compounds. The solution is added before the sintering stage, during which the ceramic acquires its final properties. In the course of this firing, the ceramic densifies and the added compounds react together as well as with the basic material of the blue Cerachrom insert to create the final black colour.This original and innovative process requires mastery of high-temperature heat treatments to closely control the deformation of the ceramic. The two-colour Cerachrom bezel insert obtained via this process presents a clear cut-off between the two colours. By virtue of being manufactured in a single piece, the insert acquires homogeneous mechanical properties which respond to the quality and reliability demanded of a Rolex product. This process has a patent pending."

