mineral

Milky Quartz

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 July 20, 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 solutions or the cooling of magma in igneous rocks. The milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative stone or landscaping gravel.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It can sometimes contain traces of gold in hydrothermal vein deposits, leading to the term 'gold-bearing quartz'.

Field identification & locations

Identify by its ability to scratch glass, its white opaque color, and lack of cleavage planes. It is found globally in almost every geological environment.