mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to light gray; 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 light gray
Luster: Vitreous to greasy

Identified May 5, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or within igneous cooling environments like pegmatites. It can be found in rocks of all geological ages.

Uses & applications

Used as an abrasive, in glass making, as a source of silicon for electronics, in landscaping, and as decorative gravel. Lower quality pieces are used in construction aggregates.

Geological facts

The white milky color is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify by its waxy/glassy look and ability to scratch glass. It is commonly found in riverbeds, mountain outcrops, and as veins within granitic rocks. Collectors look for pieces with distinct crystal points.