mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Clear to milky white; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

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

Identified April 8, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Clear to milky white; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of magma or precipitation from hydrothermal veins. It is found in all three types of rock (igneous, sedimentary, metamorphic) and is one of the most abundant minerals in Earth's crust.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, construction as a component of concrete, and as a gemstone in jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It occurs in many varieties, including amethyst, citrine, and rose quartz. It is piezo-electric, meaning it generates an electric charge when mechanical pressure is applied.

Field identification & locations

Identify in the field by its hardness (it scratches glass) and its lack of cleavage, typically breaking like shards of glass. It is commonly found in beach sand, granite outcrops, and riverbeds.