mineral

Smoky Quartz (Herkimer-style)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Smoky yellow-brown; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Smoky yellow-brown
Luster: Vitreous (glassy)

Identified April 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Smoky yellow-brown; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or pockets within sedimentary host rocks (like dolostone) where silica-rich fluids crystallized slowly over millions of years, often in the Cambrian or Ordovician periods.

Uses & applications

Used in jewelry, metaphysical healing practices, and as a popular mineral specimen for collectors.

Geological facts

This specimen is double-terminated, meaning it has natural points on both ends. This occurs when crystals grow without being attached to a matrix, suspended in a pocket of fluid or clay.

Field identification & locations

Identify by its six-sided (hexagonal) shape, double termination, and hardness. It cannot be scratched by a steel knife. Commonly found in Herkimer County, NY, or similar geological pockets globally.