mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to off-white/tan due to iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to off-white/tan due to iron staining
Luster: Vitreous to greasy

Identified July 1, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The 'milky' appearance is caused by tiny fluid or gas inclusions trapped during crystal growth. It is found in almost all geological environments and ages.

Uses & applications

Used in glass making, as an abrasive, in electronics (silicon source), as a gemstone (low value), and extensively in landscaping and construction aggregates.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. Its opacity sets it apart from rock crystal.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white/waxy appearance. Found worldwide, especially in mountain ranges and stream beds.