mineral
K-Feldspar (Potassium Feldspar)
Potassium Feldspar (Microcline or Orthoclase), KAlSi3O8
Hardness of 6 on the Mohs scale, color ranges from pink to reddish-brown and white, vitreous to pearly luster, monoclinic or triclinic crystal structure, good cleavage in two directions at approximately 90 degrees, specific gravity of 2.56-2.58.
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Physical properties
Hardness of 6 on the Mohs scale, color ranges from pink to reddish-brown and white, vitreous to pearly luster, monoclinic or triclinic crystal structure, good cleavage in two directions at approximately 90 degrees, specific gravity of 2.56-2.58.
Formation & geological history
Formed predominantly in igneous rocks like granites, pegmatites, and syenites, as well as metamorphic gneisses, through the cooling of magma or hydrothermal processes over millions of years.
Uses & applications
Used in the manufacture of ceramics, porcelain, glass, as a flux in pottery glazes, and occasionally as a minor gemstone or lapidary material.
Geological facts
Feldspars are the most abundant group of minerals in the Earth's crust, making up about 60% of terrestrial rocks.
Field identification & locations
Identified by its distinctive pink to reddish color, rectangular habit, 90-degree cleavage planes, and lack of reaction with acid. Common worldwide in granitic terrains.
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Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral