mineral

Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless to white/cloudy
Luster: Vitreous (glassy)

Identified June 30, 2026More mineral →

Explore Quartz in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. It crystallizes from magma or precipitates from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, construction (sand), and as a semi-precious gemstone in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It has been used since antiquity for making tools and decorative items. The name comes from the German word 'Quarz'.

Field identification & locations

Identified by its hardness (will scratch glass), lack of cleavage, and glassy appearance. Found globally in riverbeds, mountains, and beaches. For collectors, it is a foundational specimen.