mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent waxy; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

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

Identified June 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent waxy; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. Milky quartz specifically gets its appearance from tiny fluid or gas inclusions trapped during crystal growth in hydrothermal veins or pegmatites.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as a gemstone for cabochons and tumbled stones.

Geological facts

Milky quartz is the most common variety of crystalline quartz. The white color is caused by millions of microscopic bubbles of gas or liquid trapped within the crystal when it was forming.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and common occurrence in veins within granite or schist. It is found globally, with massive deposits in Brazil, USA, and Madagascar.