mineral

Milky Quartz (Common Quartz)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to yellowish-tan due to inclusions; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to yellowish-tan due to inclusions
Luster: Vitreous to greasy

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal fluids in veins. Milky quartz specifically gets its appearance from tiny fluid or gas inclusions trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, and as a source for silicon in electronics. In construction, it is used as road aggregate or stone fill. Lower grade specimens are common in beginner rock collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed quartz was ice that had frozen so hard it would never melt, hence the name 'krystallos' (ice).

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage. It often appears as 'vein quartz' in metamorphic or igneous terrains. It is found globally and is likely the most common mineral found by amateur collectors.

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