A PARTICULARLY RESISTANT PATENTED COMPONENT
Manufactured by Rolex from a particularly hard, corrosion-resistant ceramic, this exclusive component is virtually impervious to scratches, and its colour is unaffected by ultraviolet rays. It also offers excellent polishability ensuring an exceptional, long-lasting lustre.
For optimum legibility, the numerals and graduations are moulded in the ceramic and then coated with either a very thin layer of gold or platinum via a PVD (Physical Vapour Deposition) process.
FROM BEZEL INSERT TO MONOBLOC BEZEL
First introduced in 2005 on the GMT-Master II models, the Cerachrom bezel appears today on the Yacht-Master and Yacht-Master II, as well as on the divers’ watches: the Submariner and Submariner Date, Sea-Dweller 4000 and Rolex Deepsea. Depending on the model, the ceramic bezel insert can be black, blue or green.
Rolex has since expanded the application of this exclusive technology by introducing a new monobloc Cerachrom bezel on the Cosmograph Daytona. Extremely resistant and with peerless aesthetics, this monobloc bezel holds the crystal firmly in place, ensures waterproofness and offers an exceptionally legible tachymetric scale.
The manufacture of the Cerachrom bezel is entirely carried out in-house by Rolex. The brand has installed the exclusive equipment required to perfectly master the quality of the final product in conformity with its stringent specifications.
The basic ceramic material is a very fine zirconium dioxide or aluminium oxide powder, whose particles are less than one micron (one-thousandth of a millimetre) in diameter. It is mixed with both a binding agent that allows it to be moulded and pigments that will give the final desired colour.
The raw material is shaped by high-pressure moulding. At this point, it has very low resistance. The components are then heat treated in furnaces. The first stage eliminates the binding agent. From the second firing, or sintering, at 1,600 °C (2,900 °F), the ceramic acquires its definitive hardness and mechanical resistance. Its resistance after the sintering is akin to that of steel, but its hardness is much greater. During firing and sintering, the piece contracts by approximately 25 per cent and acquires its final colour. Final precision machining gives each piece its definitive shape and size for assembly. As the material has now acquired its characteristic hardness, this operation requires the use of diamond tools.
GOLD OR PLATINUM DEPOSITION
The surface of the Cerachrom bezel or disc is then coated, depending on the model, with a thin layer of either yellow or pink gold or platinum using a PVD process. This layer of precious metal (approximately one micron thick) also coats the moulded numerals and graduations. A final polishing removes the gold or platinum from the rest of the bezel’s surface and achieves a smooth and lustrous finish. The metal on the numerals and graduations remains, making them clearly visible. The insert is now ready to be assembled onto the bezel. The monobloc bezel, for its part, is friction fitted onto the crystal and the middle case.
COMMITMENT TO QUALITY
Throughout the production process, the Cerachrom inserts and monobloc bezels undergo countless quality controls to check the precision of their geometry, their mechanical properties and their colour. Once they have passed all the tests, the Cerachrom bezels are ready to flawlessly fulfil their purpose for many years.