mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to tan/brownish
Luster: Vitreous to greasy

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms through the hydrothermal crystallization of silica-rich fluids in veins or pegmatites. It is one of the most abundant minerals and can form in igneous, sedimentary, and metamorphic environments.

Uses & applications

Used as a source of silicon for electronics, as an abrasive, in glassmaking, as decorative landscaping stone, and occasionally for healing crystals or low-cost lapidary carvings.

Geological facts

The milky appearance is caused by tiny fluid inclusions of gas and/or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identified by its hardness (scratches glass), white/cloudy appearance, and lack of cleavage. Commonly found in riverbeds, mountains, and as vein material in many geological formations worldwide.