mineral

Milky Quartz

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

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

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

Identified June 14, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the cooling of silica-rich hydrothermal fluids in veins or as a constituent in igneous and metamorphic rocks. The 'milky' appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (as oscillators), construction aggregate, and as a decorative stone in landscaping or jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically is one of the most common varieties and is often found as 'river stones' due to its high resistance to weathering.

Field identification & locations

Identify by its white color, inability to be scratched by a steel knife, and lack of cleavage. It is found globally in riverbeds, mountains, and beaches. Collectors often use it as an indicator mineral for other deposits like gold.