mineral

Clear Quartz Crystal (Herkimer Diamond style)

Silicon Dioxide (SiO2)

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

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

Identified March 14, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in cavities or rock veins. While quartz exists from all geological ages, double-terminated specimens like this often form in soft host rock (like dolostone) or hydrothermal pockets.

Uses & applications

Extensively used in electronics (oscillators), optics, jewelry as a semi-precious gemstone, and highly popular as a metaphysical or collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Specimens that are double-terminated (pointed at both ends) like this one are often referred to as 'Herkimer Diamonds' if they originate from Herkimer County, New York.

Field identification & locations

Identify in the field by its six-sided prism shape, ability to scratch glass, and lack of cleavage. Common worldwide, but high-clarity faceted-looking crystals are frequently found in the US, Brazil, and Madagascar.

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