mineral

Quartz (Sea Glass or River-worn Pebble style)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Off-white/translucent; Luster: Vitreous to waxy (when frosted); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Off-white/translucent
Luster: Vitreous to waxy (when frosted)

Identified April 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Off-white/translucent; Luster: Vitreous to waxy (when frosted); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed through hydrothermal processes or igneous cooling. This specific specimen has been secondary-weathered by water (river or ocean) to create its smooth, frosted exterior.

Uses & applications

Used in glassmaking, electronics, silicon chips, abrasives, and as a popular collector's item for 'beach combing' enthusiasts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Specimens found on beaches or in rivers often have a frosted surface due to thousands of tiny impacts from other grains of sand and water movement.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage. Look for the smooth, rounded 'pebble' shape characteristic of water-eroded environments.

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