mineral

Quartz (Yellow/Citrine variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Yellow-brown or tan; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Yellow-brown or tan
Luster: Vitreous (glassy)

Identified June 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Yellow-brown or tan; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in igneous or metamorphic environments through hydrothermal processes. This specific specimen appears to be a water-worn or tumbled pebble of macrocrystalline quartz often found in alluvial deposits or sediment.

Uses & applications

Used extensively in glass manufacturing, electronics (due to piezoelectricity), abrasive sandblasting, and as a semi-precious gemstone in jewelry and metaphysical collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is clear, but impurities like iron or heat exposure create color variations such as citrine (yellow).

Field identification & locations

Identified by its ability to scratch glass and steel, its lack of cleavage (it breaks in curved chips), and its waxy-to-glassy luster. Commonly found in riverbeds, mountains, and deserts globally.

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