mineral

Feldspar

Potassium Feldspar (KAlSi3O8)

AI-generated identification · may be incorrect

Hardness: 6 (Mohs), Color: Pink, salmon, red, white, Luster: Vitreous to pearly, Crystal structure: Monoclinic or triclinic, Cleavage: Two directions at approximately 90 degrees

Identified August 18, 2026More mineral →

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Physical properties

Hardness: 6 (Mohs), Color: Pink, salmon, red, white, Luster: Vitreous to pearly, Crystal structure: Monoclinic or triclinic, Cleavage: Two directions at approximately 90 degrees

Formation & geological history

Formed in igneous and metamorphic rocks, often cooling from magma. Potassium feldspars are a major component of granite.

Uses & applications

Used extensively in the manufacturing of glass and ceramics. Also used as a mild abrasive and occasionally as a gemstone (e.g., moonstone, sunstone).

Geological facts

Feldspars are the most abundant group of minerals in the Earth's crust, making up about 60% of terrestrial rocks.

Field identification & locations

Identified by its pinkish color, hardness of 6 (scratches glass but not quartz), and prominent cleavage planes. Commonly found in granitic pegmatites.