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

Explanation

Quartz is a mineral that's usually clear or white, but is sometimes tinted a translucent color. It's common for quartz to be part of other rocks, and often you can see its stripes cutting through smooth beach stones. Quartz is very hard and shiny, and it's also quite common. There are many different types of quartz, and the rarest ones are considered semi-precious gemstones, like citrine and amethyst. This is the quartz that's used to make jewelry. Its chemical name is silicon dioxide, and it has a crystal structure. Quartz comes from the German Quarz, "rock crystal."

Example Sentences

Christopher joined the Journal from Quartz, where he also covered technology.

From The Wall Street Journal • Jan. 30, 2026

Sadly, her aunt turns out to be dead, but Quartz Creek’s postmaster encourages Selena to move into her house anyway.

From The Wall Street Journal • Jan. 2, 2026

In terms of trends, CBP data reported by Quartz shows that criminal arrests among CBP officers and Border Patrol reached a five-year high in 2018.

From Salon • Jul. 26, 2025

Quartz Hill 14, Antelope Valley 0: Preston White had a five-inning no-hitter.

From Los Angeles Times • Apr. 25, 2025

Quartz is the most stable and resistant to weathering.

From Earth and Sky Every Child Should Know Easy studies of the earth and the stars for any time and place by Rogers, Julia Ellen