mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Cloudy white to pale yellow/grey; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Cloudy white to pale yellow/grey
Luster: Vitreous (glassy) to greasy

Identified March 28, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Cloudy white to pale yellow/grey; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. The 'milky' appearance is caused by tiny fluid or gas inclusions trapped during crystal growth. Can be found in rocks from almost any geological age.

Uses & applications

Used in the glass and ceramic industries, as a source of silica for semiconductors, in construction as aggregate, and frequently used in lapidary work for tumbled stones and decorative carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often the most common variety found in hydrothermal veins and is a primary indicator for gold prospectors in certain regions.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and translucent 'milky' appearance. Commonly found in riverbeds, mountain outcrops, and mines globally. To identify, check for a conchoidal fracture pattern.