mineral

Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless to white (milky)
Luster: Vitreous (glassy) to greasy

Identified June 28, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. It is found in all types of geological environments and can date back billions of years depending on the host rock.

Uses & applications

Extensively used in glass making, electronics (piezoelectric properties), abrasives, construction as aggregate, and in jewelry or gemstone collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical and physical weathering, which is why it is the primary component of most beach sand.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks in curved, shell-like fractures), and its glassy luster. Extremely common worldwide, especially in granite outcrops and riverbeds.