mineral

Amethyst Cluster

Silicon Dioxide (SiO2 with iron impurities)

Hardness: 7 on Mohs scale. Color: Violet to deep purple. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal prism/pyramids). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Violet to deep purple
Luster: Vitreous (glassy)

Identified July 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed primarily in hydrothermal veins and cavity linings (geodes) inside basaltic host rocks as silica-rich water cools and crystallizes over millions of years.

Uses & applications

Widely used in gemstone jewelry, decorative crystal displays, lapidary arts, and popular in metaphysical and rock collecting circles.

Geological facts

Amethyst derives its characteristic purple color from trace amounts of iron (Fe3+) irradiated by natural background gamma radiation within the host rock. The ancient Greeks believed it prevented intoxication.

Field identification & locations

Identified by its distinctive purple color, hexagonal crystal habit with pointed terminations, and scratch resistance against steel. Commonly found in Brazil, Uruguay, Madagascar, and Thunder Bay, Canada.

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