mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Cloudy white to grayish
Luster: Vitreous to greasy

Identified April 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling and crystallization of silica-rich hydrothermal fluids or magma. Often found in hydrothermal veins, pegmatites, and as a component in many igneous rocks. Its white color is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, as an abrasive, in the production of silicon wafers for electronics, and widely as a decorative stone in landscaping or as a collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. It can sometimes contain trace amounts of gold within its veins.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and characteristic greasy luster on fractured surfaces. It is found globally in nearly every geological environment.