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What Are Fulgurites?


This is an example of a fulgurite.

Fulgurites often are glassy tubes with a rough exterior and smooth interior. The color of the fulgurite depends on the color of sand that was struck by lightning.

Luna04, Creative Commons License

Question: What Are Fulgurites?

The word fulgurite comes from the Latin word fulgur, which means thunderbolt. Fulgurites are fascinating forms created by lightning strikes.

Answer: A fulgurite is a glass tube formed when lightning strikes sand. Usually fulgurites are hollow, with a rough exterior and smooth interior. Lightning from thunderstorms makes most fulgurites, but they also form from atomic blasts, meteor strikes and from man-made high voltage devices falling onto the ground.

Fulgurite Chemistry

Fulgurites typically form in sand, which is mostly silicon dioxide. The melted sand forms a glass that is called lechatelierite. Lechatelierite is an amorphous material that is considered to be a mineraloid, similar to obsidian. Fulgurites come in a range of colors, including translucent white, tan, black and green. The coloration comes from impurities in the sand.


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