mineral

Amethyst or Smoky Quartz Geode Slice

Crystalline Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 Mohs; Color: Pale purple/greyish with smoky inclusions; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None/Conchoidal fracture.

Hardness: 7 Mohs
Color: Pale purple/greyish with smoky inclusions
Luster: Vitreous (glassy)

Identified May 2, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Pale purple/greyish with smoky inclusions; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None/Conchoidal fracture.

Formation & geological history

Formed in volcanic or sedimentary cavities (geodes) where mineral-rich hydrothermal fluids precipitate crystals over thousands of years. This specimen shows a transition from chalcedony at the base to macro-crystalline quartz.

Uses & applications

Used primarily in crystal healing, home decor, high-end lapidary work, and amateur mineral collecting.

Geological facts

The light purple tint comes from irradiation of iron impurities in the quartz structure. While this specimen is pale, amethyst is technically the state gemstone of South Carolina.

Field identification & locations

Identified by its characteristic six-sided crystal points and agate-like base. Commonly found in Brazil, Uruguay, and parts of the United States like Arizona or the Carolinas.

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