tridymite

9.9

A mineral made of the same material as sand that forms thin plate-like crystals in volcanic rock

noun
/ˈtrɪdɪˌmaɪt/

Specialized

: tridimita

Microscopic examination revealed that the thin, plate-like crystals were actually tridymite.

Examples

The presence of tridymite indicates the rock was formed at relatively low pressures and high temperatures.
The mineral tridymite is often found in volcanic rocks.
Geologists discovered a layer of tridymite in the volcanic rock samples from the region.
Some tridymites can form under high-temperature conditions.
Geologists discovered a layer of tridymite in the volcanic rock samples from the region.
Microscopic examination revealed that the thin, plate-like crystals were actually tridymite.
The presence of tridymite indicates the rock was formed at relatively low pressures and high temperatures.

Synonyms

silicate

vstridymite

Specialized

8 7.2

A common mineral in rocks and sand made from silicon and oxygen

is a specific crystalline silica form found mainly in volcanic rocks

Surface Forms

tridymite singular

tridymites plural

Morphology

tridymite = tri + dym + ite

The elements 'tri-' (three) and the mineral-forming suffix '-ite' are recognizable, but the central element is not a productive English morpheme and the precise technical meaning ('a specific silica polymorph') is not derivable by a B1 learner.

Etymology

The word tridymite comes from Greek parts tri- 'three' and didymos 'twin', a name inspired by the way its thin crystals often appear as twinned or grouped plates. So, thinking of 'three' and 'twin' helps you remember that tridymite is a form of silica that makes thin, plate-like crystals.