
mineral
K-Feldspar (Potassium Feldspar)
Potassium Feldspar (Microcline / Orthoclase, KAlSi3O8)
AI-generated identification · may be incorrectHardness: 6 on the Mohs scale. Color: Typically pink to salmon-red, sometimes white or gray. Luster: Vitreous to pearly. Crystal structure: Triclinic (Microcline) or Monoclinic (Orthoclase). Cleavage: Perfect in two directions at nearly 90 degrees. Specific gravity: 2.56-2.58.
- Hardness
- 6 on the Mohs scale
- Color
- Typically pink to salmon-red, sometimes white or gray
- Luster
- Vitreous to pearly
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Physical properties
Hardness: 6 on the Mohs scale. Color: Typically pink to salmon-red, sometimes white or gray. Luster: Vitreous to pearly. Crystal structure: Triclinic (Microcline) or Monoclinic (Orthoclase). Cleavage: Perfect in two directions at nearly 90 degrees. Specific gravity: 2.56-2.58.
Formation & geological history
Forms primarily in igneous rocks like granite, pegmatites, and syenites, as well as in metamorphic rocks through crystallization from cooling magma or high-temperature hydrothermal processes.
Uses & applications
Used in the manufacturing of ceramics, porcelain, glass, and as a mild abrasive in scouring powders. Specimen collectors value unique crystal formations.
Geological facts
Feldspars are the most abundant group of minerals in the Earth's crust, making up about 60% of the crust. The distinctive pink color is often caused by microscopic hematite inclusions.
Field identification & locations
Easily identified by its pinkish-red color, rectangular cleavage, and lack of reaction to acid. Commonly found in granitic pegmatites worldwide.
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