Imagine carving solid gold. Well, the same effect has been produced here by carving wood and coating it with a layer of gold by electroforming. It is possible to build up the thickness of the gold to several millimeters or until it becomes self-supporting. Many types of metal can be applied as 'coatings' in this way. Used in the production of finely detailed film props, like armour and masks, it is the most practical way of reproducing such intricate parts in metal.
Image from MPFDP