rock crystal

American  

noun

1. transparent quartz, especially when colorless.

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rock crystal British  

noun

1. a pure transparent colourless quartz, used in electronic and optical equipment. Formula: SiO 2

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Etymology

Origin of rock crystal

First recorded in 1660–70

Example Sentences

Surely the brilliant carving was executed with the aid of a magnifying lens, perhaps made from a piece of rock crystal.

From Los Angeles Times

As winds whip around the planet, carrying along the quartz nanoparticles, they form high-altitude hazes — essentially diffuse clouds of rock crystals — at the day–night termination zone.

From Scientific American

She was buried with ivory tusks, ostrich eggshell, and a rock crystal dagger.

From BBC

It held a rock crystal dagger, ivory tusks and other lavish items.

From Seattle Times

Among the finds have been a Swiss leather shoe over 3,500 years old and a 10,000-year-old Alpine glacier mine where hunters once extracted rock crystals to make arrowheads and other kinds of blades.

From Washington Post