The chemical composition and physical properties of jadeite and nephrite are given as are the geographical origins ofjade simulants such as Transvaaljade (grossular garnet), Queensland jade (chrysoprase) and Pilbara jade (a chlorite). The artistic use of jade in China and elsewhere is discussed as is the Maori use of nephrite (a variety of serpentinite). Australian jade comes from two major deposits of nephrite discovered in the mid 1960's. -- AATA