Audemars Piguet

European Watch Clock and Jewellery Fair 1988 BF 210
The world’s first tantalum watch : its selfwinding chronograph movement with 21K gold centre rotor is lodged inside a tantalum and pink gold case fitted with a croco strap with foldaway clasp. Tantalum is a rare metal, akin to platinum but more blueish and impervious to acids. Its melting point is about 30000 C. (AUDEMARS PIGUET)