mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: milky white to translucent grey; Luster: vitreous to greasy; Crystal Structure: trigonal/hexagonal; Cleavage: none (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: milky white to translucent grey
Luster: vitreous to greasy

Identified July 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: milky white to translucent grey; Luster: vitreous to greasy; Crystal Structure: trigonal/hexagonal; Cleavage: none (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of geological environments, most commonly in hydrothermally formed veins, pegmatites, and igneous rocks like granite as silica-rich fluids cool and crystallize.

Uses & applications

Used in electronics, glassmaking, gemstones, abrasive materials, silica sand for construction, and extensively in rock collecting and decorative items.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The white, opaque appearance of milky quartz is caused by tiny gas or liquid bubbles trapped inside the crystal during its formation.

Field identification & locations

Identify in the field by its hardness (scratches glass easily, cannot be scratched by a steel knife), lack of cleavage, vitreous luster, and milky white translucency. Extensively found worldwide in riverbeds, gravels, and mountainous regions.