mineral
Feldspar
Triclinic or Monoclinic Tectosilicate (e.g., KAlSi3O8)
Hardness of 6 on the Mohs scale, color ranges from white, gray, pink to yellow, vitreous to pearly luster, prismatic crystal structure, good two-way cleavage at approximately 90 degrees, specific gravity of 2.5 to 2.7.
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Physical properties
Hardness of 6 on the Mohs scale, color ranges from white, gray, pink to yellow, vitreous to pearly luster, prismatic crystal structure, good two-way cleavage at approximately 90 degrees, specific gravity of 2.5 to 2.7.
Formation & geological history
Formed in igneous rocks like granite and pegmatites, as well as metamorphic and sedimentary environments through the cooling and crystallization of magma or alteration processes.
Uses & applications
Used extensively in the manufacture of glass, ceramics, pottery glazes, and as a flux in metallurgy.
Geological facts
Feldspar is the most abundant mineral group in the Earth's crust, making up about 60% of the terrestrial rocks.
Field identification & locations
Identified in the field by its rectangular crystal habit, 90-degree cleavage planes, and hardness that scratches glass. Commonly found in granitic pegmatites worldwide.
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Regolith / Silicate Mineral Aggregate
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Limonite / Goethite (Iron Ore Mineral nodule)
FeO(OH)·nH2O / FeO(OH)
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Septarian Pebble
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Schist
Schist
Metamorphic
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral