mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: White/Opaque. Luster: Vitreous to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: Poor/Conchoidal fracture. Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White/Opaque
Luster: Vitreous to greasy

Identified June 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: White/Opaque. Luster: Vitreous to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: Poor/Conchoidal fracture. Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or within igneous pegmatites. The milky appearance is caused by tiny fluid or gas inclusions trapped during crystal growth. This specimen shows significant rounding from river or beach erosion.

Uses & applications

Used in glass making, electronics (piezoelectric properties), abrasives, and as decorative landscaping stone. High-purity quartz is essential for silicon chip manufacturing.

Geological facts

Quartz is the most abundant and widely distributed mineral found at Earth's surface. Milky quartz is the most common variety. Ancient Greeks believed quartz was ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its white color, inability to be scratched by a steel knife, and distinctive conchoidal (shell-like) fracture patterns. Commonly found in riverbeds, beaches, and soil worldwide.