mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified April 15, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal veins or the cooling of magma in igneous rocks. The milky color is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), landscaping, abrasives, and as a raw material for silicon production. Often collected as a decorative stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), its lack of cleavage, and its waxy or vitreous luster. Commonly found in river beds and mountainous regions globally.