We know all the most famous materials for watch cases — titanium, steel, gold, rose gold, etc. Many watch brands take a legitimate pride in creating their own movements, cases and dials. But some of them invent their own components, mostly for use in cases, but sometimes even for details inside the timepieces. Rolex is among them. The brand invests a lot of money in inventing its own alloys by mixing various metals.
Rolesium is one of the metals invented by Rolex. The material is a combination of 950 platinum and 904L stainless steel superalloy. Rolesium was used in the 40-mm diameter Oyster case of the Rolex Yacht Master.
Rolex also invented Cerachrom. It is a corrosion-resistant and extra-hard ceramic. This material has used on the bezels of the 50th Anniversary Rolex Cosmograph Daytona and the Rolex Submariner.
Rolex Cosmograph Daytona was presented at Baselworld two years ago. Cerachrom bezels have carved numerals and graduations covered with a thin layer of platinum via a physical vapor deposition (PVD) process.
The 50th Anniversary Rolex Cosmograph Daytona has other material developed by Rolex. It is blue Parachrom. A hairspring in the model movement made of it. This material is used because it is uncommonly resistant to magnetic fields. Parachrom is an alloy of zirconium, niobium and oxygen. Hairsprings made of this alloy stay firm through temperature changes and be much less accessible to shocks, staying, on the basis of the Rolex statement, 10 times more precise in case of shocks than a conventional hairspring.