mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 18, 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; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or pegmatites; milky appearance is caused by microscopic fluid inclusions trapped during growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative stones or in jewelry (cabochons).

Geological facts

Milky quartz is the most common variety of crystalline quartz. The white 'milky' color is actually the result of millions of tiny gas and liquid bubbles trapped within the crystal as it formed.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and waxy/vitreous luster. Commonly found in gold-bearing veins and metamorphic terrains worldwide.