Feldspars are a family of minerals that occur in various rock types. They are aluminosilicates that can be pink, gray, white, or brown in color. Some of the synonyms for feldspars include microcline, orthoclase, plagioclase, anorthite, albite, and oligoclase. Microcline is a type of potassium feldspar that occurs in granite and pegmatite rocks. Orthoclase is another potassium feldspar that is commonly found in igneous and metamorphic rocks. Plagioclase feldspar is formed from a mixture of sodium and calcium and is commonly found in basalts and gabbros. Anorthite is a calcium-rich feldspar that occurs in moon rocks and some volcanic rocks. Albite is a sodium feldspar that is commonly found in granites and pegmatites.