mineral

Fulgurite

Lechatelierite (vitreous silica)

Mohs hardness of 5.5 to 6; color ranges from white, tan, grayish-brown to black; vitreous to greasy luster; amorphous crystal structure; specific gravity around 2.1 to 2.2.

Identified August 1, 2026More mineral →

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Physical properties

Mohs hardness of 5.5 to 6; color ranges from white, tan, grayish-brown to black; vitreous to greasy luster; amorphous crystal structure; specific gravity around 2.1 to 2.2.

Formation & geological history

Formed when lightning strikes sand, soil, or rock with temperatures exceeding 1,800 to 3,000 degrees Celsius, instantly melting and fusing the material into a hollow, glassy tube.

Uses & applications

Prized by mineral collectors and researchers studying ancient atmospheric conditions; sometimes used in jewelry or educational displays.

Geological facts

Fulgurites are often called 'petrified lightning'. They can extend several meters deep into the earth depending on the voltage and soil composition.

Field identification & locations

Found in sandy deserts, beaches, and high-altitude mountain peaks where lightning strikes frequently. Look for fragile, glassy, tubular structures protruding from sand or soil.