mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified March 16, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide range of environments including igneous, metamorphic, and sedimentary rocks. It crystallizes from silica-rich magma or precipitates from hydrothermal veins. It is found in deposits ranging from Precambrian to recent geological ages.

Uses & applications

Used in electronics (oscillators), optical instruments, glass manufacturing, abrasives, jewelry (as gemstones), and widely collected by mineral enthusiasts for aesthetic and metaphysical purposes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed clear quartz was 'krystallos' (ice) that had become permanently frozen.

Field identification & locations

Identify in the field by its hardness (scratches glass), six-sided prismatic crystals terminating in pyramids, and lack of cleavage. Commonly found in pegmatites, hydrothermal veins, and as sand in riverbeds worldwide.