mineral

Quartz (Quartz Pebble)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Colorless to milky translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to milky translucent
Luster: Vitreous to greasy

Identified July 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to milky translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of geological environments including igneous pegmatites, metamorphic rocks, and hydrothermal veins. Water-worn pebbles are smoothed by stream or river erosion.

Uses & applications

Used extensively in gemstone carving, lapidary arts, electronics (piezoelectric crystals), glassmaking, abrasives, and as mineral specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz, historically called rock crystal, was thought by ancient Greeks to be permanently frozen ice.

Field identification & locations

Identified by its scratch hardness (scratches glass easily), lack of cleavage, conchoidal fracture, and glassy luster. Commonly found in riverbeds, beach gravels, and pegmatite deposits worldwide.