Jade is a kind of tremolite jade, which is a kind of nephrite formed by serpentine intruding into basic volcanic rocks and other surrounding rocks. It is a kind of chalcedony with more impurities, in which the content of iron oxide and clay minerals can reach more than 20%. It is opaque, and its color is mostly dark red, green or variegated.
In addition to Kunlun Mountains, North America and Oceania, nephrite in the world also produces Jasper. In Xinjiang jade market, there are Russian Jasper, Canadian Jasper, Hotan Jasper and Mahe Jasper.