feldspar

n. any of a group of alumino-silicates (Mineralogy)

Feldspar is the name of a group of rock-forming minerals which make up as much as 60% of the Earth's crust.Feldspars crystallize from magma in both intrusive and extrusive rocks, and they can also occur as compact minerals, as veins, and are also present in many types of metamorphic rock. Rock formed entirely of plagioclase feldspar (see below) is known as anorthosite. Feldspars are also found in many types of sedimentary rock.
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Noun
1. any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium
(synonym) felspar
(hypernym) spar
(hyponym) orthoclase
(substance-meronym) silicon, Si, atomic number 14

Any of a group of light-colored, silicate, rock-forming minerals most often found in plutonic igneous rocks and metamorphic rocks and often containing potassium, sodium, or calcium. Feldspar constitutes 60% of the Earth's crust.

fldsp