FELDSPAR

feldspar, felspar

(noun) any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium

Source: WordNet® 3.1


Etymology

Noun

feldspar (countable and uncountable, plural feldspars)

(mineral) Any of a large group of rock-forming minerals that, together, make up about 60% of the earth's outer crust. The feldspars are all aluminum silicates of the alkali metals sodium, potassium, calcium and barium. Feldspars are the principal constituents of igneous and plutonic rocks.

Source: Wiktionary


Feld"spar`, Feld"spath`, n. Etym: [G. feldspath; feld field + spath spar.] (Min.)

Definition: A name given to a group of minerals, closely related in crystalline form, and all silicates of alumina with either potash, soda, lime, or, in one case, baryta. They occur in crystals and crystalline masses, vitreous in luster, and breaking rather easily in two directions at right angles to each other, or nearly so. The colors are usually white or nearly white, flesh-red, bluish, or greenish.

Note: The group includes the monoclinic (orthoclastic) species orthoclase or common potash feldspar, and the rare hyalophane or baryta feldspar; also the triclinic species (called in general plagioclase) microcline, like orthoclase a potash feldspar; anorthite or lime feldspar; albite or soda feldspar; also intermediate between the last two species, labradorite, andesine, oligoclase, containing both lime and soda in varying amounts. The feldspars are essential constituents of nearly all crystalline rocks, as granite, gneiss, mica, slate, most kinds of basalt and trachyte, etc. The decomposition of feldspar has yielded a large part of the clay of the soil, also the mineral kaolin, an essential material in the making of fine pottery. Common feldspar is itself largely used for the same purpose.

Source: Webster’s Unabridged Dictionary 1913 Edition



RESET




Word of the Day

2 April 2025

COVERT

(adjective) secret or hidden; not openly practiced or engaged in or shown or avowed; “covert actions by the CIA”; “covert funding for the rebels”


coffee icon

Coffee Trivia

“Coffee, the favorite drink of the civilized world.” – Thomas Jefferson, third president of the United States

coffee icon