True or false? Lightning turns sand into glass

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by: Alysa Carsley

Posted: Jun 28, 2022 / 02:44 PM EDT

Updated: Jun 28, 2022 / 02:44 PM EDT

SAVANNAH, Ga. (WSAV) – I was visiting a school about two years ago when a group of kids asked about a myth: when lightning hits the sand, it turns into glass.

At that time, I hadn’t heard of this magical fable. But I looked it up when I got back, and now, I incorporate it in my true and false game during school visits.

So now, you can be part of the fun…

Answer: It’s true (sort of). It’s not the type of glass you might immediately think of, like a window. It looks more like a tree branch.

Now stick with me here…

When lightning strikes sand, it can turn into fulgurite (also known as fossilized lightning). Lightning creates a tube of glass below the ground. Eventually, the sand above it moves around and the glass tubes are revealed. However, it is very hard to find due to both lightning and sand needing to hit specific criteria for it to form.

Lightning has to be 3,272 degrees Fahrenheit or hotter and the sand has to be high in silica or quartz. If both are in perfect conditions, then the heat from the bolt fuses the sand into a silica glass beneath the ground.

It has an interesting look — a hard, gray, sand-like outside texture.

The inside is where you find the glass. Clear or whitish glass tubes form when the molten sand cools quickly.

Again, this is rare. Plus, our coastline doesn’t have the correct type of sand.

While Tybee and Hilton Head islands have silica grained sand, they have too many shells, preventing the perfect scenario for fulgurite to form.

LIGHTNING SAFETY: If you hear thunder, leave the beach immediately and seek shelter. Even if the storm seems far away, lightning can still extend up to 15 miles outside a storm.

Wait at least 30 minutes from the last rumble of thunder before heading back onto the beach.

true (sort of)LIGHTNING SAFETY:

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