Rock Identifier
Pink feldspar fragment (probable orthoclase or microcline) (Potassium feldspar, KAlSi₃O₈) — mineral
mineral

Pink feldspar fragment (probable orthoclase or microcline)

Potassium feldspar, KAlSi₃O₈

AI-generated identification · may be incorrect

Small salmon-pink, opaque fragment with a dull-to-pearly luster and irregular, partly cleavage-controlled surfaces. Feldspar hardness is about 6 Mohs, with two cleavages near 90°; crystal structure is monoclinic (orthoclase) or triclinic (microcline), and specific gravity is about 2.55–2.63.

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Physical properties

Small salmon-pink, opaque fragment with a dull-to-pearly luster and irregular, partly cleavage-controlled surfaces. Feldspar hardness is about 6 Mohs, with two cleavages near 90°; crystal structure is monoclinic (orthoclase) or triclinic (microcline), and specific gravity is about 2.55–2.63.

Formation & geological history

Crystallizes from cooling silica-rich magma in granites, pegmatites, and related metamorphic rocks; potassium feldspar commonly formed during Precambrian to younger geologic events. The pictured piece may be naturally broken or tumbled/abraded.

Uses & applications

Used extensively in glass and ceramic manufacture and as a component of construction aggregate; attractive crystals are collected, though this small fragment has minimal gem value.

Geological facts

The salmon-pink color typically comes from tiny hematite inclusions or lattice defects. Feldspar is the most abundant mineral group in Earth’s crust.

Field identification & locations

Check for two intersecting cleavage planes, hardness sufficient to scratch glass, and a nonmetallic pink color; it should not fizz in dilute acid. Common sources include granite regions and pegmatites worldwide, especially Madagascar, Brazil, India, and the United States.