mineral
Quartz (Herkimer Diamond variant)
Silicon Dioxide (SiO2)
Hardness: 7 on Mohs scale; Color: Colorless to smoky with internal inclusions; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture.
- Hardness
- 7 on Mohs scale
- Color
- Colorless to smoky with internal inclusions
- Luster
- Vitreous (glassy)
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Physical properties
Hardness: 7 on Mohs scale; Color: Colorless to smoky with internal inclusions; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture.
Formation & geological history
Formed in vugs or cavities of the Little Falls Dolostone (sedimentary) during the Cambrian Period roughly 500 million years ago. These crystals grew slowly in pockets of water containing dissolved silica.
Uses & applications
Highly valued as mineral specimens for collectors; used in jewelry and by the metaphysical community for 'healing' practices.
Geological facts
Despite the name, they are not diamonds but double-terminated quartz crystals. They are famous for their exceptional clarity and natural multifaceted shape.
Field identification & locations
Identify by its double-terminated (pointed at both ends) shape and extreme clarity compared to standard quartz. Primarily found in Herkimer County, New York, and surrounding areas.
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