mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (trapezohedral); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glassy)

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the cooling and solidification of silica-rich magma or from hydrothermal solutions. It occurs in all geological ages and is common in igneous, metamorphic, and sedimentary environments, ranging from mountain veins to riverbeds.

Uses & applications

Extensively used in electronics (oscillators and clocks) due to piezoelectric properties. In jewelry, it is used as a gemstone (Rock Crystal). Also used in glass making, abrasives, and as a popular specimen for mineral collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the Greeks believed it was ice that had frozen so hard it would never melt. It is the most common mineral used in 'healing crystals' and metaphysical practices.

Field identification & locations

Identify in the field by its hardness (it can scratch glass and steel), lack of cleavage, and hexagonal crystal shape if intact. Common locations include the Alps, Brazil, Madagascar, and Arkansas (USA). For collectors, look for clarity and the absence of internal fractures.