mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to translucent with orange/brown iron staining, Luster: Vitreous to greasy, Crystal Structure: Hexagonal (trigonal), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 11, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins, pegmatites, and as a constituent of igneous rocks. It crystallizes from silica-rich fluids underground. This specimen shows iron oxide staining common in surface-exposed minerals.

Uses & applications

Used as a source of silicon for electronics, an abrasive in glass making and sandpaper, construction aggregate, and in landscaping or as collector specimens.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. The white 'milky' color is caused by millions of tiny fluid inclusions (bubbles of gas or liquid) trapped during the crystal's growth.

Field identification & locations

Identify by its hardness (it will easily scratch glass) and lack of cleavage. Found globally in almost all geological environments. Iron-stained 'rusty' quartz like this is often a sign of nearby mineralization for gold prospectors.