mineral

Quartz (Milky/Bull Quartz)

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to translucent gray
Luster: Vitreous (glassy) to greasy

Identified March 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling and solidification of magma or through hydrothermal processes where silica-rich fluids precipitate in rock veins. Quartz is found in almost all geological ages due to its chemical stability.

Uses & applications

Used in the production of glass, ceramics, and abrasives. High-purity quartz is essential in electronics and silicon chip manufacturing. It is also used in construction as aggregate and occasionally as ornamental stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its characteristic white color from microscopic fluid inclusions of gas and liquid trapped during the crystal's growth.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass but cannot be scratched by a steel knife) and its lack of cleavage. It is found globally, common in pegmatites and metamorphic veins. For collectors, look for well-defined crystal faces or unique mineral associations.