mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Colorless to transparent white. Luster: Vitreous (glass-like). Crystal Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Colorless to transparent white
Luster: Vitreous (glass-like)

Identified July 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Colorless to transparent white. Luster: Vitreous (glass-like). Crystal Structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments, most commonly crystallized in hydrothermal veins and pegmatites during cooling of silica-rich magma.

Uses & applications

Widely used in gemstone jewelry, ornamental carvings, glassmaking, electronics (piezoelectric applications in quartz watches), and crystal collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed clear quartz was ice frozen so deeply that it would never melt, calling it 'krystallos'.

Field identification & locations

Can be identified by its glassy clarity, hardness (scratches glass and steel), and lack of cleavage. Commonly found in stream beds, pegmatites, and geodes worldwide.