mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Identified February 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silicon-dioxide rich hydrothermal solutions crystallizing in veins or igneous intrusions. The milky appearance is caused by tiny fluid inclusions (gas or liquid bubbles) trapped during crystal growth. Can form across various geological ages.

Uses & applications

Used commercially in glassmaking, abrasives, and as a source of silicon for electronics. In geology, it is often a decorative stone, landscaping material, or collector specimen. High-quality quartz is used in timekeeping (oscillators).

Geological facts

Milky quartz is one of the most common mineral varieties on the Earth's crust. Ancient Greeks once believed quartz was ice that had frozen so hard it would never melt.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white translucent color. Commonly found in mountain ranges, stream beds, and quartz veins within granite or schist.