mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified June 25, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the cooling of silica-rich hydrothermal fluids in veins or pegmatites. The white color is caused by tiny inclusions of gas or liquid trapped during crystal growth. Can be found in rocks from almost any geological age.

Uses & applications

Used in glass making, ceramics, abrasives, and as a source of silicon for electronics. Found in landscaping and as a decorative stone or for metaphysical collecting.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It often contains microscopic fluid inclusions that give it its cloudy appearance, and it is frequently associated with gold in hydrothermal vein deposits.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel blade), lack of cleavage, and translucent-to-opaque white appearance. It is ubiquitous in riverbeds, mountains, and as garden gravel.