gemstone

Clear Quartz (Rock Crystal)

Crystalline Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified July 9, 2026More gemstone →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in igneous, metamorphic, and sedimentary environments through hydrothermal activity or the cooling of silica-rich magma/fluids. Found in veins and geodes globally.

Uses & applications

Used in jewelry as a gemstone, in glassmaking, as a frequency control in electronics (piezoelectric properties), and as a popular collector specimen.

Geological facts

Ancient Greeks called quartz 'krystallos', meaning 'ice', believing it was water permanently frozen by the gods. It is the second most abundant mineral in the Earth's continental crust.

Field identification & locations

Identify by its clarity, ability to scratch glass (hardness 7), and lack of cleavage. This specific specimen appears to be a faceted or step-cut gemstone, possibly set in a bezel-style mounting.