mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: White to opaque
Luster: Vitreous to greasy

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to opaque; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; 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 or gas inclusions trapped during crystal growth. Can be found in all types of geological environments.

Uses & applications

Used in glassmaking, jewelry (as beads or cabochons), landscaping, as an abrasive, and in the production of silicon wafers for the electronics industry.

Geological facts

Milky quartz is the most common variety of crystalline quartz. While often overlooked by collectors for more colorful stones, its opacity makes it a distinct geological marker.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and characteristic white waxy appearance. Commonly found as pebbles in stream beds or as veins in igneous or metamorphic outcrops.