M MineralystRock & Mineral Guide
Mineral

Orthoclase Feldspar

Orthoclase Feldspar — reference photo

Orthoclase Feldspar is a mineral with the chemical formula KAlSi3O8. It has a Mohs hardness of 6 - 6.5 and vitreous luster.

Orthoclase Feldspar properties

TypeMineral
Chemical formulaKAlSi3O8
Mohs hardness6 - 6.5
LusterVitreous
Typical colorsTypically white, pink, or orange; can also be colorless or green.
FormationForms primarily in igneous rocks like granite and as a constituent of many metamorphic rocks.
Rarity3 / 10

Mohs hardness 6–6.5 — fairly hard

1 · Talc5 · Apatite10 · Diamond
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