mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: White, cream, or translucent gray. Luster: Vitreous to greasy. Crystal structure: Trigonal (often massive in pebbles). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White, cream, or translucent gray
Luster: Vitreous to greasy

Identified April 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary mineral in igneous rocks like granite. This specimen has been rounded by fluvial (river) or glacial erosion over thousands of years.

Uses & applications

Used in glassmaking, abrasives, construction aggregate, and as a source of silicon for electronics. Smooth pebbles are often used in landscaping and aquariums.

Geological facts

The milky appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. Quartz is the second most abundant mineral in the Earth's continental crust.

Field identification & locations

Identified by its ability to scratch glass and lack of cleavage. Look for it in riverbeds, beaches, and gravel pits globally. It is a common 'leaverite' for seasoned collectors but a great beginner find.