mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: White to cloudy-opaque. Luster: Vitreous (glassy) to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to cloudy-opaque
Luster: Vitreous (glassy) to greasy

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: White to cloudy-opaque. Luster: Vitreous (glassy) to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can range from billions of years old to a few million years old depending on the geological deposit.

Uses & applications

Used in glassmaking, as an abrasive in sandblasting, in the production of silicon chips (electronics), and common in jewelry or landscape decoration.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many cultures to create tools and weapons due to its hardness and ability to hold a sharp edge when fractured.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel) and lack of cleavage planes. Found globally in almost all geological environments, particularly in mountain ranges and river beds. For collectors, look for pieces with interesting surface textures or associations with other minerals.