A loosely applied term for a variety of metamorphosed basic igneous rocks of a green color: serpentine, olivine, jade, jadeite, nephrite, chloromelanite, etc. The general term is useful, though, since ancient man used these materials interchangeably, mainly for high quality or ceremonial polished stone axes, figures, and other objects. Jade was particularly popular in China and Middle America, considered to have magical properties. Greenstone was important in southeastern Australia and in New Zealand. The green color comes from the minerals chlorite, hornblende, or epidote.