quartz

American  

[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.

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quartz British  

/ 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: SiO 2 . Crystal structure: hexagonal

2. short for quartz glass

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quartz Scientific  

/ kwôrts /

1. 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: SiO ₂ .

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Other Word Forms

• quartzose adjective
• quartzous adjective

Etymology

Origin of quartz

First recorded in 1750–60, quartz is from the German word Quarz

Example Sentences

Boomers upgraded to stainless and quartz, put in a pool, added a couple of bedrooms—and made that house harder to afford.

From Barron's • Mar. 14, 2026

South Africa, long renowned for its mineral wealth, saw a similar frenzy in 2021 when crystal‑like stones found in KwaZulu-Natal province sparked a diamond rush, only for experts to confirm they were merely quartz.

From Barron's • Feb. 16, 2026

“The formal dining area is perfect for entertaining beneath an elegant chandelier, while the kitchen features chic quartz countertops and ample storage,” the listing reads.

From MarketWatch • Feb. 4, 2026

At each location, the team identified shocked quartz -- grains of sand that have been physically altered by extreme heat and pressure.

From Science Daily • Jan. 1, 2026

The piece of quartz was resting solidly at the bottom of his pocket, but he couldn’t reach it.

From "The Reader" by Traci Chee