mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: 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: White to translucent
Luster: Vitreous (glassy) to greasy

Identified February 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: 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 crystallization of magma or from hydrothermal veins. It can originate in almost any geological environment (igneous, metamorphic, or sedimentary) over billions of years of Earth's history.

Uses & applications

Used in the manufacturing of glass, electronics (piezoelectric properties), abrasives, and as a component in concrete. Often used in landscaping and low-to-mid range gemstone jewelry.

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 often remains as sand on beaches after other minerals have eroded.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife and its lack of cleavage. It is found globally, common in mountain ranges and riverbeds. Look for 'glassy' shards that do not break along flat planes.