Fulgurite
“Lightning frozen in stone”
Fulgurite forms when lightning strikes sand, soil, or rock, instantly melting the material at temperatures exceeding 30,000°C and fusing it into a glassy, tubular structure. These fragile natural sculptures preserve the exact path the lightning bolt took through the ground.
lechatelierite (amorphous silica glass), partially melted quartz, other fused minerals
Sahara Desert, Florida beaches (USA), sand dunes worldwide, anywhere lightning strikes sandy ground
5-7 (glassy exterior)
The longest fulgurite ever excavated was over 4.9 meters long, found in northern Florida — but fulgurites may extend much deeper and simply break apart when dug up.
Test Your Knowledge
At what temperature does lightning fuse sand into fulgurite glass?
Related Specimens
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