The case is one of the most important features of a watch. Even though the case does not contribute to timekeeping, it is indispensable for any watch and one of the supporting elements in terms of design. Watch cases can be designed very differently, depending on the type. Floor and wall clocks usually have a case made of wood and steel, often also of bronze or glass, while pocket watches always have a case made of metal. Wristwatches can have both metal and plastic cases, whereby high-quality watches are usually made of precious metals. Watches whose cases are partly made of genuine silver or gold are therefore not a minority. The case of a watch serves to keep dirt away from the mechanical parts of the watch and to protect the delicate parts inside from shocks. The case is also the visible part of a watch, which means that a great deal of attention is also paid to the design during manufacture. In addition to the precious metals already mentioned, aluminium, platinum or titanium are also frequently used in the manufacture of valuable watches.