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feld·spar(fĕld′spär′, fĕl′-) also fel·spar (fĕl′-)
Any of a group of abundant rock-forming minerals occurring in igneous, metamorphic, and sedimentary rocks, and consisting of silicates of aluminum with potassium, sodium, calcium, and, rarely barium. About 60 percent of the earth's outer crust is composed of feldspar.
feldspar(ˈfɛldˌspɑː; ˈfɛlˌspɑː) or
(Minerals) any of a group of hard rock-forming minerals consisting of aluminium silicates of potassium, sodium, calcium, or barium: the principal constituents of igneous rocks. The group includes orthoclase, microcline, and the plagioclase minerals
[C18: from German feldspat(h), from feld field + spat(h) spar3]
feldspathic, felˈspathic, ˈfeldspathˌose, ˈfelspathˌose adj
any of a group of crystalline minerals, principally aluminosilicates of potassium, sodium, and calcium, characterized by two cleavages at nearly right angles: one of the most important constituents of igneous rocks.
[1765–75; alter. of feldspath < German (Feld field + Spat(h) spar)]
Any of a group of abundant minerals consisting of silicates of aluminum with potassium, sodium, and calcium. Feldspars range from white, pink, or brown to grayish blue in color. They occur in igneous, sedimentary, and metamorphic rocks and make up more than 60 percent of the Earth's crust.
Any of a group of minerals comprising aluminum silicates and a metal (calcium, potassium, or sodium).
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|Noun||1.||feldspar - any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium|
atomic number 14, Si, silicon - a tetravalent nonmetallic element; next to oxygen it is the most abundant element in the earth's crust; occurs in clay and feldspar and granite and quartz and sand; used as a semiconductor in transistors
orthoclase - a white or colored monoclinic feldspar
moonstone - a transparent or translucent gemstone with a pearly luster; some specimens are orthoclase feldspar and others are plagioclase feldspar
spar - any of various nonmetallic minerals (calcite or feldspar) that are light in color and transparent or translucent and cleavable