mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms through crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. It is found in many geological environments globally across all ages.

Uses & applications

Used in glassmaking, ceramics, and as an abrasive. Large, clean pieces are used in jewelry and lapidary art. It is also a common specimen for rock collectors.

Geological facts

The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on Earth.

Field identification & locations

Identify by its white, opaque color, glass-like luster where broken, and its ability to easily scratch glass. Usually found in veins within granite or metamorphic rocks.