low tridymite

mineral

Also known as: alpha-tridymite, low-tridymite

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June 30, 2026

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Low tridymite is a mineral form of silica (SiO₂) that is stable at temperatures between 870° and 1,470° C. It is one of three modifications of tridymite, alongside high-tridymite and middle-tridymite. Tridymite itself is a polymorph of silica, meaning it shares the same chemical composition as other silica minerals like quartz and cristobalite but has a different crystal structure.123

Tridymite typically forms thin, hexagonal plates, often twinned. It is commonly found in igneous rocks, such as trachytes, and can also be present in meteorites. Tridymite is a silicate mineral, a large group of silicon-oxygen compounds that are abundant in Earth's crust and upper mantle.145

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tridymite
…three modifications: high-tridymite, middle-tridymite, and low-tridymite. Tridymite forms thin hexagonal plates that are generally twinned, often in groups of three; its name alludes to this habit. It commonly occurs in igneous rocks, more abundantly than cristobalite, as in the trachytes of Rhineland-Palatinate, Germany; northern Italy; and in the Massif Central,…
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…three modifications: high-tridymite, middle-tridymite, and low-tridymite. Tridymite forms thin hexagonal plates that are generally twinned, often in groups of three; its name alludes to this habit. It commonly occurs in igneous rocks, more abundantly than cristobalite, as in the trachytes of Rhineland-Palatinate, Germany; northern Italy; and in the Massif Central,…
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