mineral

Quartz Pebble (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to translucent
Luster: Vitreous to waxy

Identified April 19, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in veins or as a major constituent of igneous rocks like granite. This specific specimen has been polished smooth by water erosion (river or beach action) or a rock tumbler.

Uses & applications

Used in glassmaking, ceramics, as an abrasive, in decorative landscaping, and occasionally as a low-cost gemstone or healing crystal in the metaphysical market.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (H=5.5) and its lack of cleavage planes. Found globally in almost all geological environments, especially riverbeds and beaches.

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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