mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale. Color: Colorless and transparent. Luster: Vitreous/Glassy. Crystal system: Trigonal/Hexagonal. Cleavage: Indistinct (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless and transparent
Luster: Vitreous/Glassy

Identified April 4, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale. Color: Colorless and transparent. Luster: Vitreous/Glassy. Crystal system: Trigonal/Hexagonal. Cleavage: Indistinct (conchoidal fracture). Specific gravity: 2.65.

Formation & geological history

Formed through the crystallization of magma or by precipitation from hydrothermal veins. It occurs in all geological environments and across all ages, often forming in pockets where silica-rich fluids cool.

Uses & applications

Used in electronics for its piezoelectric properties, glass manufacturing, abrasives, jewelry (as semi-precious stones), and widely collected for metaphysical or decorative purposes.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. Pure specimens are perfectly clear and were once believed by ancient Greeks to be ice that had frozen so hard it would never melt.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and conchoidal (shell-like) fracture. Commonly found in granite, sandstone, and pegmatites worldwide, particularly in Brazil and Arkansas, USA.