mineral

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)

Hardness: 7.5 on Mohs scale; Color: Clear to smokey; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (doubly terminated); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7
Color: Clear to smokey
Luster: Vitreous (glassy)

Identified May 29, 2026More mineral →

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Physical properties

Hardness: 7.5 on Mohs scale; Color: Clear to smokey; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (doubly terminated); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in cavities within the Little Falls Dolostone during the Cambrian period, approximately 500 million years ago, through slow precipitation from hydrothermal fluids.

Uses & applications

Primarily used in jewelry, as mineral specimens for collectors, and in metaphysical practices.

Geological facts

They are called 'diamonds' due to their natural faceting and high clarity, though they are actually quartz. They are unique for being naturally doubly terminated, meaning they have points on both ends without being cut.