mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale); Color: Opaque white to creamy; Luster: Vitreous to waxy (when water-worn); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: Opaque white to creamy
Luster: Vitreous to waxy (when water-worn)

Identified May 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich hydrothermal fluids or within magma. This specific specimen is a river-worn or beach-worn pebble, meaning it underwent mechanical weathering and transport over thousands of years to achieve its rounded shape.

Uses & applications

Used as a source for silicon in glass making, electronics, and construction aggregates. Rounded pebbles are popular in landscaping and as pocket stones for collectors.

Geological facts

The milky white color is caused by tiny inclusions of gas or liquid trapped during the crystal's initial formation. It is one of the most abundant minerals on Earth's crust.

Field identification & locations

Identify by its hardness (it will scratch glass) and lack of cleavage. Commonly found in riverbeds, glacial tills, and beaches worldwide. Collectors should look for smoothness and consistent opacity.