mineral

Milky Quartz

Silicon dioxide (SiO2)

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

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

Identified April 25, 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 prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or during the cooling of igneous magmas. Milky quartz gets its cloudiness from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used widely in glassmaking, abrasives, as a flux in metallurgy, in the production of silicon for electronics, and as a semi-precious gemstone or decorative stone in landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature.

Field identification & locations

Identify in the field by its hardness (will scratch glass), white color, and lack of cleavage. It is ubiquitous globally, often found in mountain ranges and riverbeds.