mineral

Milky Quartz

Quartz (Silicon Dioxide) - SiO2

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to greasy

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the cooling of silica-rich magma or from hydrothermal veins. The white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth. They can be found in rocks from almost any geological age.

Uses & applications

Used in the glassmaking industry, as an abrasive, in the production of silicon metal, and for landscaping. In jewelry, it is often used for cabochons or beads, though it is usually considered a low-value gemstone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of crystalline quartz. Historically, it has been used for stone tools and as a decorative building material.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and white 'milky' appearance. It is found globally in pegmatites, hydrothermal veins, and as pebbles in riverbeds. Beginners can identify it by its inability to be scratched by a steel knife.