tridymite
/ˈtrɪdɪmaɪt/
noun
- A mineral form of silica (silicon dioxide) that occurs in volcanic rocks and meteorites.
- Tridymite is sometimes used in the production of heat-resistant ceramics.
- Geologists found tridymite crystals in the volcanic ash layer.
- The presence of tridymite in the rock sample indicates high-temperature formation.