microcline

A whitish gray, pink or green triclinic mineral of the potassium feldspar group that forms from relatively low-temperature magmas.

A feldspar identical in composition with orthoclase, but belonging to the triclinic system.

A mineral of the feldspar group, like orthoclase or common feldspar in composition, but triclinic in form.

A common feldspar of igneous, plutonic, and metamorphic rocks, made of potassium aluminum silicate, with the chemical formula KAlSi3O8. Microcline is the main feldspar of granite. The bluish-green variety is called amazonstone, and is sometimes of gem quality. Used in ceramics, ceramic glazes, and as a scouring powder.