mineral

Potassium Feldspar (Microcline)

KAlSi3O8

Hardness of 6 on the Mohs scale, typically pink, peach, or white in color, vitreous to pearly luster, monoclinic or triclinic crystal structure, perfect cleavage in two directions at nearly right angles, specific gravity around 2.56-2.58.

Identified August 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the slow cooling of magma in igneous environments, particularly in granites, pegmatites, and syenites, often crystallizing during the later stages of magma cooling over millions of years.

Uses & applications

Widely used in the manufacturing of ceramics, porcelain, and glass, as well as in the production of scouring powders and fertilizers; minor use as a gemstone.

Geological facts

Feldspars are the most common mineral group in the Earth's crust, making up about 60% of the crust. The pink color in potassium feldspar is typically caused by microscopic hematite inclusions.

Field identification & locations

Identified by its characteristic salmon-pink or peach color, blocky crystal habit, and the presence of cleavage planes that reflect light. Commonly found in pegmatite dikes and granitic rock outcrops worldwide.