mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO₂)

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to greasy

Identified March 16, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; 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 from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used extensively in the glass industry (silica sand), electronics (piezoelectric properties), abrasives, construction aggregates, and semi-precious jewelry or decorative carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German 'Quarz', which has Slavic origins meaning 'hard'. It is famous for its piezoelectric property, meaning it can generate an electric charge in response to applied mechanical stress.

Field identification & locations

Identify in the field by its hardness (will easily scratch glass) and lack of cleavage. Look for characteristic conchoidal (shell-like) fractures. It is commonly found in riverbeds, mountains, and as boulders in soil worldwide.