mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 3, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal solutions or cooling of magma in pegmatites. It is one of the most common minerals in the Earth's crust, found in various geological ages ranging from billions of years old to recent formations.

Uses & applications

Used as a source of silica for glassmaking, as an abrasive in sandpaper, in high-frequency oscillators for electronics, as ornamental stone in landscaping, and sometimes in low-grade jewelry or carvings.

Geological facts

The milky white color is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. It is the official state mineral of several regions and is famously found in mass quantities as 'bull quartz' in gold-bearing veins.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and translucent white appearance. Commonly found in quartz veins, riverbeds, and as boulders in glacial till. It is a key indicator for prospectors as it often hosts gold veins.