mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: white to cloudy; Luster: vitreous (glassy) to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: none (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: white to cloudy
Luster: vitreous (glassy) to greasy

Identified May 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: white to cloudy; Luster: vitreous (glassy) to greasy; Crystal Structure: Hexagonal (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 white color is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. Can be found in almost all geological environments.

Uses & applications

Used in glass making, abrasives, as a component in concrete, electrical oscillators, and in the production of silicon metal. Lower grade specimens are used in landscaping and as crushed stone; higher grade for jewelry (cabochons) or carving.

Geological facts

Quartz is one of the most abundant minerals in the Earth's continental crust. Milky quartz is the most common variety of crystalline quartz. It is often found in gold-bearing veins, making it a primary indicator for gold prospectors.

Field identification & locations

Identify in the field by its hardness (will easily scratch glass) and lack of cleavage. Look for white, opaque masses or crystals in igneous or metamorphic host rocks. It is found globally in mountains, riverbeds, and beach sands.