Only the very finest materials are used in IWC watch cases. Each of these materials has its own specific properties and offers certain advantages. Timeless and of lasting value, gold is the embodiment of luxury and elegance. For its gold cases, IWC uses 18-carat gold, containing 75 per cent of the pure metal. Since pure gold would be too soft for use in a watch case, it is alloyed with other metals, which also gives it the desired colour: palladium for white gold, or silver and copper for 5N gold.