mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

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

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

Identified June 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in vein deposits or cooling magma. This particular specimen is a water-worn pebble likely eroded from a larger vein and weathered over millions of years.

Uses & applications

Used in the manufacturing of glass, electronics (piezoelectric properties), abrasives, and as decorative aggregate in landscaping and construction.

Geological facts

Milky quartz gets its white color from tiny fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and white 'milky' appearance. Found globally in riverbeds, beaches, and mountain soil. Collectors often look for it as an indicator of other minerals like gold in vein deposits.