mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to creamy white; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to creamy white
Luster: Vitreous to greasy

Identified July 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to creamy white; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

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

Uses & applications

Used as an abrasive, in glass making, as a gemstone (cabochons), in landscaping, and as a source of silicon for electronics. Primarily valued by collectors as a common decorative mineral.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is often found in massive form rather than distinct crystals. Because of its hardness, it often survives long periods of erosion, which is why it is so common in riverbeds and soil.

Field identification & locations

Identified in the field by its white color, inability to be scratched by a steel knife, and its characteristic conchoidal (shell-like) fracture. It is ubiquitous worldwide, especially in mountainous regions and gravel deposits.