mineral

Quartz (Grain)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Colorless to white (transparent), Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified July 11, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Colorless to white (transparent), Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Quartz forms in all types of geological environments: igneous (crystallizing from cooling magma), sedimentary (as resistant grains in sand/sandstone), and metamorphic (recrystallized in rocks like quartzite). This specific grain appears to be a detrital grain from weathered rock.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, construction sand, and as a gemstone when found in larger crystals.

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 is the primary component of most beach sand.

Field identification & locations

Identified in the field by its hardness (scratches glass), glass-like appearance, and lack of cleavage. Common in riverbeds, beaches, and various rock outcrops worldwide.