Quartz

[kwawrts] /kwɔrts/

noun
1.
one of the commonest minerals, silicon dioxide, SiO 2 , having many varieties that differ in color, luster, etc., and occurring either in masses (as agate, bloodstone, chalcedony, jasper, etc.) or in crystals (as rock crystal, amethyst, citrine, etc.): the chief constituent of sand and sandstone, and an important constituent of many other rocks. It is piezoelectric and used to control the frequencies of radio transmitters.
/kwɔːts/
noun
1.
a colourless mineral often tinted by impurities, found in igneous, sedimentary, and metamorphic rocks. It is used in the manufacture of glass, abrasives, and cement, and also as a gemstone; the violet-purple variety is amethyst, the brown variety is cairngorm, the yellow variety is citrine, and the pink variety is rose quartz. Composition: silicon dioxide. Formula: SiO2. Crystal structure: hexagonal
2.
short for quartz glass
n.

“silicon dioxide,” 1756, from German Quarz, Zwarc “rock crystal,” from Middle High German twarc, probably from a West Slavic source, cf. Czech tvrdy, Polish twardy “quartz,” noun uses of an adjective meaning “hard,” from Old Church Slavonic tvrudu “hard,” from Proto-Slavic *tvrd-, from PIE *(s)twer- “to grasp, hold; hard.”

quartz (kwôrts)
n.
A very hard crystalline form of silicon dioxide used in chemical apparatus and in optical and electric instruments.
quartz
(kwôrts)
A hard, transparent trigonal mineral that, after feldspar, is the most common mineral on the surface of the Earth. It occurs as a component of igneous, metamorphic, and sedimentary rocks as well as in a variety of other forms such as rock crystal, flint, and agate. Some crystalline forms, such as amethyst, are considered gemstones. Chemical formula: SiO2.