mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Colorless and transparent. Luster: Vitreous (glass-like). Crystal Structure: Hexagonal (trigonal). Cleavage: None, exhibits conchoidal fracture. Specific Gravity: 2.65.

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

Identified July 24, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, most commonly in pegmatites, hydrothermal veins, and metamorphic rocks through the crystallization of silica-rich fluids as they cool.

Uses & applications

Used extensively in jewelry, ornamental carvings, electronics (piezoelectric oscillators), optics, and highly sought after by mineral collectors and metaphysical enthusiasts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz was historically believed by ancient Greeks to be ice that was permanently frozen into stone (hence the word 'krystallos', meaning ice).

Field identification & locations

Identified in the field by its hexagonal crystal habit, glassy luster, conchoidal fracture, and ability to scratch glass easily (Mohs hardness 7). Commonly found worldwide, with high-quality specimens coming from Brazil, Arkansas (USA), and the Alps.