... major components are quartz ,feldspar, diopside , tremolite , actinolite and etc , which is recrystallized after silicification . It's origin ... in China , we are the legal and sole supplier for this black and white Hua'an Jade in the world ... & lucky symbolization . Steady physical and chemical property, waterproof ,acid and alkali resistance ,wear and corrosion resisting ,also prevent from mildewing ...