Potassium Feldspar

Potassium Feldspar is a generic name for three very closely related minerals: Orthoclase, Sanidine, and Microcline. These three Feldspar minerals have equal physical properties. They are all composed of the same elements, but their crystal structure slightly differs. It is sometimes impossible to tell apart one of these minerals from another without x-ray analysis. Because of this, all these three minerals may be simply called "Potassium Feldspar". Sanidine and Microcline are also wrongly classified as a variety of Orthoclase in many reference guides, when, in fact, they are separate minerals.
Anorthoclase is usually classified with the potassium feldspars.

Synonyms for Potassium Feldspar include: