sedimentary

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Off-white to pale tan. Luster: Dull to vitreous. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Off-white to pale tan
Luster: Dull to vitreous

Identified July 25, 2026More sedimentary →

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Physical properties

Hardness: 7 on Mohs scale. Color: Off-white to pale tan. Luster: Dull to vitreous. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: ~2.65.

Formation & geological history

Formed through weathering, erosion, and stream transport of silica-rich rocks, resulting in rounded water-worn pebbles.

Uses & applications

Used in construction aggregate, landscaping, decorative stone, and as raw material for silica extraction.

Geological facts

Quartz is one of the most abundant minerals on Earth's surface and is highly resistant to both chemical and mechanical weathering.

Field identification & locations

Identified by its high hardness (scratches glass), smooth water-worn surface, light color, and lack of distinct cleavage. Common in riverbeds, beaches, and gravel deposits worldwide.