orthoclase feldspar

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Related to orthoclase feldspar: microcline, adularia, biotite

orthoclase feldspar:

see feldsparfeldspar
or felspar
, an abundant group of rock-forming minerals which constitute 60% of the earth's crust. Chemically the feldspars are silicates of aluminum, containing sodium, potassium, iron, calcium, or barium or combinations of these elements.
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