
mineral
Potassium Feldspar (Orthoclase / Microcline)
KAlSi3O8 (Potassium Aluminum Silicate)
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, reddish-orange to pinkish-tan color with pearly to vitreous luster, two cleavage planes at nearly 90 degrees, triclinic or monoclinic crystal system.
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Physical properties
Hardness of 6 on Mohs scale, reddish-orange to pinkish-tan color with pearly to vitreous luster, two cleavage planes at nearly 90 degrees, triclinic or monoclinic crystal system.
Formation & geological history
Forms primarily in felsic igneous rocks like granite and pegmatites through slow crystallization of magma, as well as in high-grade metamorphic rocks.
Uses & applications
Used extensively in the ceramic and glass industries, as a dimension stone, and occasionally as a gemstone or specimen for collectors.
Geological facts
Feldspars make up over 50% of Earth's crust by weight. Pink or reddish feldspar is responsible for the distinct color of pink granite rocks.
Field identification & locations
Identified by its distinctive salmon-pink/orange color, hardness that scratches glass but yields to quartz, and blocky cleavage surfaces with cleavage lines.