mineral

Clear Quartz (Herkimer Diamond variant)

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 March 7, 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 from hydrothermal activity where silica-rich fluids permeate into cavities within host rocks. While quartz spans all geological ages, specific double-terminated versions like this are often found in Cambrian-aged dolostone (approx. 500 million years old).

Uses & applications

Commonly used in jewelry (rings, pendants), as metaphysical healing crystals, in watchmaking (piezoelectric properties), and as an abrasive in industrial glass manufacturing.

Geological facts

This specimen is a 'double-terminated' crystal, meaning it grew into points on both ends rather than being attached to a matrix. While often called 'Herkimer Diamonds,' that specific name technically only applies to those found in Herkimer County, New York.

Field identification & locations

Identify in the field by its six-sided (hexagonal) prism shape and lack of cleavage. It is commonly found in Arkansas, New York, and Brazil. Collectors look for clarity, sharp terminations, and the absence of internal inclusions.

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