Feldspar is the most common mineral found at the surface of the earth. There are two basic varieties of feldspar: Orthoclase (Potassium Feldspar) and Plagioclase (Calcium-Sodium Feldspar). The term feldspar came from German meaning “field split.” Very well named as feldspars have a bad property for gemstones-perfect cleavage. Here are some of the most common […]