mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: semi-transparent, milky white to grey; Luster: vitreous (glassy) to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: none (conchoidal fracture).

Hardness: 7 (Mohs scale)
Color: semi-transparent, milky white to grey
Luster: vitreous (glassy) to waxy

Identified May 17, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: semi-transparent, milky white to grey; Luster: vitreous (glassy) to waxy; Crystal structure: Hexagonal/Trigonal; Cleavage: none (conchoidal fracture).

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. This specific specimen appears to be water-worn, smoothed by erosion in a river or marine environment over thousands of years.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as decorative gravel or gemstones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it often survives as rounded pebbles.

Field identification & locations

Identified by its ability to scratch glass and lack of cleavage. Commonly found in riverbeds, beaches, and soil. Collectors look for clarity and unique inclusions.