mineral

Bismuth Crystal

Bismuth (element symbol Bi, atomic number 83)

Hardness: 2.25 on Mohs scale; Color: Iridescent rainbow colors due to oxidation; Luster: Metallic; Crystal Structure: Trigonal (hopper-shaped crystals); Cleavage: Perfect; Specific Gravity: 9.78

Hardness: 2
Color: Iridescent rainbow colors due to oxidation
Luster: Metallic

Identified May 24, 2026More mineral →

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Physical properties

Hardness: 2.25 on Mohs scale; Color: Iridescent rainbow colors due to oxidation; Luster: Metallic; Crystal Structure: Trigonal (hopper-shaped crystals); Cleavage: Perfect; Specific Gravity: 9.78

Formation & geological history

Laboratory-grown through a slow-cooling process of molten bismuth metal. Native bismuth in nature is typically silver-white and lacks the hopper structure and rainbow colors seen in synthetic specimens.

Uses & applications

Used primarily in jewelry and as decorative collector specimens. Industrially, bismuth is used in cosmetics, medicines (like Pepto-Bismol), and low-melting alloys.

Geological facts

Bismuth is one of the few substances that is more dense as a liquid than as a solid. It is also the most naturally diamagnetic element and has low toxicity compared to neighboring heavy metals like lead.

Field identification & locations

Identify by its unique 'hopper' crystal shape (stepped, square-like structures) and vibrant iridescent tarnish. While native bismuth is found in Australia, Bolivia, and China, these colorful lab-grown crystals are the most common form in collections.

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