Mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to opaque cream, often with iron staining (orange/brown); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal (though this specimen is massive/non-crystalline in form); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The 'milky' appearance is caused by millions of tiny microscopic inclusions of gas or liquid trapped during crystal growth. Found in geological environments ranging from Precambrian to recent eras.

Uses & applications

Used industrially as a source of silicon for semiconductors, glass making, and abrasives. In construction, it is crushed for road base or used as decorative landscaping stone. Also popular among metaphysical collectors and as garden decor.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. In the past, it was often discarded by miners as 'barren quartz' unless it was found to contain veins of gold.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife, its lack of cleavage (it breaks in irregular, curved shards), and its white, waxy appearance. Commonly found in mountainous regions, riverbeds, and as 'float' in soil. It is a key indicator mineral for prospectors looking for gold-bearing veins.