Technical ceramics used in watchmaking have nothing to do with earthenware: they are sintered zirconium oxide or alumina at extremely high temperatures, materials with a hardness that exceeds stainless steel on the Vickers scale. The practical result is a surface that resists daily scratches in a way no traditional metal can match, and that maintains its original color over time without oxidizing or fading under UV rays.
The production process is demanding. Ceramic powders are pressed into molds, sintered in an oven, and then machined with diamond tools, because at that point the material is too hard for any conventional cutter. Producing entire cases in ceramics requires precise tolerances already at the mold stage, because shrinkage during sintering is significant and irregular. Achieving uniform color across consistent production batches remains a real technical challenge: black is relatively manageable, white is more difficult, saturated colors like red or blue require strict control of powder composition.
Every major house has developed its own variant. Rolex calls its bezel insert Cerachrom, used on Submariner, GMT-Master and Daytona: it is resistant to UV rays and abrasion, and engravings are filled with gold or platinum via PVD. IWC patented Ceratanium, a titanium alloy fired to assume hard ceramic properties on its surface while maintaining the lightness and workability of titanium; it uses it for cases, crowns and pushers. Hublot with Magic Gold reversed the operation: it infiltrated ceramic into an 18-karat gold structure to create the first scratch-resistant gold, introduced in 2011. Rado is probably the brand that pushed deepest into structural ceramic use: monobloc case, bezel insert and bracelet in high-tech ceramic, with a plasma treatment that transforms classic black into a gray with an almost metallic appearance.
The possible finishes on ceramic are polished, satin and microblasted. The latter is obtained by projecting abrasive microspheres onto the surface, creating a tactile matte particularly used on watches with an instrumental vocation. Ceramic also appears in internal components: in the IWC Ingenieur 82600 caliber, zirconium oxide parts reduce wear in gears. Lumicast, used by Farer, is a ceramic and Super-LumiNova composite that allows creating applied indices more robust than simple liquid lume filling. HyCeram, used by Artime, appears in the chapter ring and at the tips of the hands. The grand feu technique applies enamel to ceramic plates for highly durable dials. Ceramics, in short, is not a single material: it is a family, and each variation is born from a precise compromise between hardness, weight, workability and cost.