Ceramics are lighter and harder than steel, scratch-resistant and have a velvety surface. These properties make it ideal for use in wristwatches. Technical ceramics are based on polycrystalline powders such as silicates, aluminium oxide or silicon carbide. They are mixed with additives, shaped to a so-called “green body”, machined close to the final geometry and then sintered at high temperatures in a kiln. During this process, the additives vaporize and leave behind extremely stable ceramic bodies. The manufacture of a ceramic watch case is particularly demanding because the material shrinks by about a third during the baking process. This shrinkage must be factored in as early as the design phase.