mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

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

Identified March 18, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Formation & geological history

Formed through the cooling and crystallization of silica-rich magma or from hydrothermal solutions in veins. It is found in all geological ages and in igneous, metamorphic, and sedimentary environments.

Uses & applications

Used widely in glassmaking, electronics (piezoelectric properties), precision clocks, high-end jewelry (as Rock Crystal), and for decorative or holistic collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the ancient Greeks believed clear quartz was ice that had frozen so hard it would never melt, hence the name 'krystallos'.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and hexagonal prism habit if in raw form. Commonly found in riverbeds, mountains, and pegmatites worldwide (Brazil and Arkansas are top sources).