mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

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

Identified May 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (trigonal); 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 found in igneous, metamorphic, and sedimentary environments globally and can be of almost any geological age from Precambrian to modern.

Uses & applications

Used extensively in glass making, electronics (piezoelectric properties), abrasives, as a flux in metallurgy, and in watches. Rough specimens are common in the landscaping and gravel industries.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from microscopic inclusions of fluids that were trapped during the crystal's growth.

Field identification & locations

Identify in the field by its hardness (will scratch glass/steel), lack of cleavage (looks like broken glass), and characteristic white to clear color. Common in riverbeds, mountains, and as vein material in many rock types.