mineral

Potassium Feldspar (Orthoclase Pebble)

KAlSi3O8 (Potassium aluminum silicate)

AI-generated identification · may be incorrect

Hardness 6 on Mohs scale, peachy-pink to salmon color, vitreous to pearly luster, and monoclinic crystal system with characteristic nearly right-angle cleavage planes.

Identified September 25, 2026More mineral →

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Physical properties

Hardness 6 on Mohs scale, peachy-pink to salmon color, vitreous to pearly luster, and monoclinic crystal system with characteristic nearly right-angle cleavage planes.

Formation & geological history

Crystallized from silica-rich igneous melts such as granites and pegmatites, then shaped and smoothed into a pebble by mechanical weathering and fluvial erosion.

Uses & applications

Commonly used in the manufacture of ceramics, porcelain, and glass, as well as an abrasive or tumbled pocket stone for hobbyists.

Geological facts

Feldspars make up roughly 60% of Earth's crust. Its name derives from the German 'Feld' (field) and 'Spat' (rock that easily flakes).

Field identification & locations

Identifiable by its distinct salmon-pink color, hardness capable of scratching glass, and lack of reaction with dilute acid. Abundantly found in gravels, granitic terrains, and riverbeds globally.