mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: White to translucent cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal (often found as massive chunks); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to translucent cloudy
Luster: Vitreous to greasy

Identified March 22, 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 cloudy appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. High-purity quartz is used in electronics for oscillators. Occasionally used as decorative stones in landscaping or as low-cost gemstones/beads.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While it lacks the clarity of rock crystal, it is chemically identical. It is incredibly resistant to weathering, which is why it is often found as smooth pebbles in riverbeds or as prominent outcroppings on hillsides.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (hardness 7) and its lack of cleavage planes. It is found globally in igneous, metamorphic, and sedimentary environments. Collectors look for large, well-formed hexagonal points, though 'massive' chunks like this are very common.