mineral

Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Clear to white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to white
Luster: Vitreous (glassy)

Identified July 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of magma or by hydrothermal precipitation from hot water solutions in veins. It is found in igneous, metamorphic, and sedimentary environments worldwide.

Uses & applications

Used extensively in electronics for frequency control, glassmaking, abrasives, construction as sand, and as a gemstone for jewelry and ornamental carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it can generate an electric charge when mechanical pressure is applied.

Field identification & locations

Identify by its hardness (it will scratch glass), its lack of cleavage, and common six-sided prismatic crystals. It is found almost everywhere, particularly in mountainous regions and riverbeds.