mineral
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
Hardness: 7 (Mohs scale), Color: Colorless to smoky, Luster: Vitreous/Adamantine, Structure: Hexagonal (doubly terminated), Cleavage: None/Conchoidal fracture, SG: 2.65
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Physical properties
Hardness: 7 (Mohs scale), Color: Colorless to smoky, Luster: Vitreous/Adamantine, Structure: Hexagonal (doubly terminated), Cleavage: None/Conchoidal fracture, SG: 2.65
Formation & geological history
Formed in Dolostone cavities (vugs) approximately 500 million years ago during the Cambrian Period. Slow cooling allowed for double termination.
Uses & applications
Collecting, jewelry, and metaphysical use. Valued for its natural diamond-like clarity and shape.
Geological facts
They are not actually diamonds; they are double-terminated quartz crystals. They were first discovered by settlers in Little Falls, New York in the late 18th century.
Field identification & locations
Look for double-terminated points in Dolostone host rock. Found primarily in Herkimer County, New York and surrounding areas.
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