mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Chalky white to cream
Luster: Vitreous to greasy

Identified June 15, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed during the final stages of hydrothermal crystallization or in pegmatites. The milky white opacity is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass making, as an abrasive, in the production of silicon chips, as garden landscaping stone, and occasionally in jewelry as cabochons.

Geological facts

Quartz is the most abundant mineral in Earth's continental crust. Milky Quartz is specifically the most common variety found in nature and often contains small amounts of gold in hydrothermal veins.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its common association with granite or metamorphic rocks. It is frequently found in riverbeds as rounded 'river rocks'.