mineral

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to opaque; Luster: Vitreous to greasy; Crystal structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

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

Identified June 20, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to opaque; Luster: Vitreous to greasy; Crystal structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through hydrothermal activity where silica-rich hot fluids circulate through fractures in crustal rocks, precipitating quartz as they cool. These veins can form in igneous, metamorphic, or sedimentary host rocks over millions of years.

Uses & applications

Quartz is used in glassmaking, electronics (as oscillators due to piezoelectric properties), abrasives, and as a common gemstone or landscaping material. Large milky quartz boulders are often used for decorative garden features.

Geological facts

Milky quartz gets its white, cloudy appearance from tiny inclusions of gas or liquid trapped during the crystal's growth. It is one of the most common minerals on Earth's surface and is highly resistant to chemical weathering.

Field identification & locations

Identify in the field by its hardness (will easily scratch glass or steel), white color, and distinctive greasy luster on fresh breaks. It is ubiquitous in mountainous regions and riverbeds worldwide. Collectors look for hydrothermal 'pockets' where well-formed crystals may sit.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

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metamorphic

Nephrite Jade

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

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mineral