Instead of being just one mineral, Feldspar is a group of aluminosilicate (a silicate in which aluminum replaces some of the silicon) minerals that contain calcium, sodium, or potassium. Feldspars are broken down into two main groups, Plagioclase Feldspars and Alkali Feldspars (sometimes referred to as Potassium Feldspars).

Feldspars make up more than 50% of the minerals in the earth’s crust. They have many industrial uses depending on the type but feldspars also comprise several gemstones including moonstone, sunstone, labradorite, amazonite, and andesine.