mineral

Fulgurite

Lechatelierite

Hardness: 6.5-7 on Mohs scale; Color: Grey, brown, black, or tan; Luster: Vitreous to dull; Crystal structure: Amorphous silica glass (silicon dioxide); Specific gravity: 2.1-2.2

Hardness: 6
Color: Grey, brown, black, or tan
Luster: Vitreous to dull

Identified August 3, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Grey, brown, black, or tan; Luster: Vitreous to dull; Crystal structure: Amorphous silica glass (silicon dioxide); Specific gravity: 2.1-2.2

Formation & geological history

Formed when a lightning strike hits sandy or rocky soil, instantly melting and fusing the material at extremely high temperatures (over 1,800 degrees Celsius).

Uses & applications

Collectible specimen, educational display, and sometimes used in metaphysical practices.

Geological facts

Commonly referred to as 'fossilized lightning', fulgurites often form hollow glass tubes that mirror the path of the electrical discharge through the ground.

Field identification & locations

Found in sandy deserts, beaches, or high-altitude mountain peaks struck by lightning. Collectors look for fragile, hollow, glass-lined tubular structures.