tridymite

American  

[trid-uh-mahyt] / ˈtrɪd əˌmaɪt /

noun

Mineralogy.

1. a polymorph of quartz occurring in the form of small crystals, commonly twinned, in siliceous volcanic rocks.

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Etymology

Origin of tridymite

1865–70; < German Tridymit, equivalent to tridym- ( Greek trídym ( os ) triple, equivalent to tri- tri- + ( dí ) dymos didymous ) + -it -ite ¹

Example Sentences

The temperatures were still relatively high: we know they must have been around 600°C, because the garnets formed alongside a high-temperature version of quartz called tridymite.

From Scientific American

It was tridymite, a mineral that is rare on Earth and has never seen before on Mars.

From New York Times

When crystalline grains or blebs of quartz occur, we have a quartz-trachyte; when tridymite is abundant, as in the trachyte of Co.

From Project Gutenberg

It was of the texture and roughness of granite, but more heavily shot with quartz, or tridymite than any other granite he'd ever seen.

From Project Gutenberg

As they cooled, they sometimes fractured, and tridymite ended up growing in their cracks.

From Scientific American