mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: White to opaque (milky). Luster: Vitreous to greasy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to opaque (milky)
Luster: Vitreous to greasy

Identified March 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: White to opaque (milky). Luster: Vitreous to greasy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can be found in rocks from almost any geological age.

Uses & applications

Used in the glass industry, as an abrasive, in the production of silicon, and as a semi-precious gemstone in jewelry or for decorative landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky Quartz specifically is often associated with gold deposits in 'quartz veins.' In ancient times, some believed quartz was permanently frozen ice.

Field identification & locations

Identify in the field by its hardness (it can easily scratch glass) and lack of cleavage. It is found globally, particularly in mountainous regions, riverbeds, and as part of granite. Common everywhere from North America to the Alps.