mineral

Milky Quartz

Silicon Dioxide (SiO2)

Mohs hardness: 7. Color: translucent white/cloudy. Luster: vitreous (glassy) to waxy. Crystal system: Hexagonal/Trigonal. Cleavage: Poor/Conchoidal fracture. Specific gravity: 2.65.

Hardness: 7
Color: translucent white/cloudy
Luster: vitreous (glassy) to waxy

Identified July 15, 2026More mineral →

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Physical properties

Mohs hardness: 7. Color: translucent white/cloudy. Luster: vitreous (glassy) to waxy. Crystal system: Hexagonal/Trigonal. Cleavage: Poor/Conchoidal fracture. Specific gravity: 2.65.

Formation & geological history

Forms through the crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. It can be found in almost any geological environment including mountainous metamorphic terrains and sedimentary deposits.

Uses & applications

Used in glass making, ceramics, and as an abrasive. In jewelry, it is used for beads and cabochons. Massive quartz is also used in construction as aggregate and in the electronics industry for its piezoelectric properties.

Geological facts

The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. Quartz is the second most abundant mineral in Earth's continental crust.

Field identification & locations

Identify by its hardness (it scratches glass), conchoidal fracture, and lack of visible cleavage planes. It is often found as veins in other host rocks or as pebbles in stream beds.