mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified April 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is found in all types of geological environments and can be from any geological age, though major deposits often date back millions of years.

Uses & applications

Used in electronics (as oscillators), glassmaking, abrasives, jewelry (gemstones), and as decorative collector specimens. It is also used in 'healing crystal' practices.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is perfectly clear, but impurities can turn it into amethyst, citrine, or smoky quartz.

Field identification & locations

Identify in the field by its hardness (it can scratch glass and steel), its conchoidal (shell-like) fracture, and distinctive hexagonal prism shapes if crystals are intact. Commonly found in mountains, riverbeds, and as a component in many rocks.