mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Identified June 2, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide variety of environments, most commonly from the cooling of magma or by hydrothermal precipitation from hot fluids in veins. It is found in rocks of all ages.

Uses & applications

Used extensively in glassmaking, electronics (piezoelectric properties), abrasives, and as a component in concrete. In jewelry, it is used for beads and carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as rock crystal, while milky quartz gets its appearance from tiny fluid inclusions trapped during growth.

Field identification & locations

Identify by its hardness (will scratch glass and steel), lack of cleavage, and six-sided crystal habits. It is ubiquitous globally, found in nearly every geological environment.