mineral

Milky Quartz (Water-Worn Pebble)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: Opaque white to creamy white with iron staining. Luster: Vitreous (glassy) to waxy. Crystal Structure: Hexagonal (Trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Opaque white to creamy white with iron staining
Luster: Vitreous (glassy) to waxy

Identified March 2, 2026More mineral →

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Physical properties

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent of igneous rocks. This specific specimen has been smoothed and rounded over thousands to millions of years by fluvial (river) or marine (beach) erosion.

Uses & applications

Common quartz is used in the glass-making industry, as an abrasive, and in construction as aggregate. Large, clear specimens are used in jewelry and electronics (piezoelectric properties), while pebbles like this are popular for landscaping and aquarium decor.

Geological facts

Milky quartz gets its white appearance from microscopic inclusions of liquid or gas trapped during the crystal's formation. It is the most common variety of crystalline quartz found on Earth's crust.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (it will scratch the steel instead), its white 'waxy' appearance, and Lack of cleavage planes. Found globally in riverbeds, glacial deposits, and mountain ranges.

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