mineral

Fulgurite

Lechatelierite (Silica glass tube)

Hardness: 5.5 to 6 on the Mohs scale, Color: Tan, grey, white, or brownish, Luster: Vitreous to dull, Crystal structure: Amorphous (glass)

Hardness: 5
Luster: Vitreous to dull, Crystal structure: Amorphous (glass)

Identified July 31, 2026More mineral →

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Physical properties

Hardness: 5.5 to 6 on the Mohs scale, Color: Tan, grey, white, or brownish, Luster: Vitreous to dull, Crystal structure: Amorphous (glass)

Formation & geological history

Formed when a high-voltage lightning strike (typically 30,000+ amperes) hits silica-rich sand or soil, instantly melting and fusing the grains together at temperatures exceeding 1,500 to 2,000 degrees Celsius.

Uses & applications

Prized by collectors, educational displays, and sometimes used in jewelry or metaphysical practices.

Geological facts

Fulgurites are often called 'fossilized lightning'. They are delicate tubular structures and can be found in deserts, beaches, and sandy regions worldwide.