Amethyst Geode

Physical Properties

Hardness: 7 (Mohs scale), Color: Purple to deep violet, Luster: Vitreous (glassy), Structure: Hexagonal crystal system, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & Geological History

Formed within volcanic rocks (basalts) as gas bubbles trap mineral-rich hydrothermal fluids. Over millions of years, crystals grow inward from the cavity walls.

Uses & Applications

Predominantly used for ornamental purposes, healing stones, high-end jewelry, and as a staple in mineral collections.

Geological Facts

The purple color is the result of irradiation and iron impurities within the quartz crystal lattice. It was once considered as valuable as diamonds until large deposits were found in Brazil.

Field Identification & Locations

Look for a dull, potato-like exterior (rhyolite or basalt) that sounds hollow when tapped. Crystals are only visible once the geode is cracked or sliced open.

Identified on: 4/21/2026

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