mineral

Clear Quartz

Silicon Dioxide (SiO2)

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

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Quartz forms in a wide variety of environments, most commonly by cooling from molten silica (magma) or precipitating from hydrothermal veins. The location reported (Minas Gerais, Brazil) is world-famous for high-quality quartz crystals and pegmatites.

Uses & applications

Extensively used in electronics (oscillators), glassmaking, abrasive materials, jewelry, and as decorative metaphysical specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge when mechanical pressure is applied, which is why it is used in watches and radios.

Field identification & locations

Identified by its ability to scratch glass, its lack of cleavage (it breaks in smooth, curved shell-like fractures), and its vitreous luster. This specimen appears to be 'Rock Crystal,' the purest form of quartz.