Fulgurite-Lightning Captured in the Sand

Fulgurite at Jockey's Ridge State Park, Nags Head.
Fulgurite at Jockey’s Ridge State Park, Nags Head.
Fulgurite a Delicate, Intricate Shape of Lightning

The Outer Banks week is looking like it’s going to be a bit stormy for a couple of days. The forecast doesn’t look too bad toward the end of the week though.

With the storms, if there is lightening, comes the possibility of a remarkable phenomenon—fulgurite.

Created by lightning when it strikes the sand, fulgurite may be more common than we realize, but finding it seems like a rare event.

There are probably a couple of reasons why it is seen so rarely. Knowing what to look for is a big part of that. Shaded slightly darker than the surrounding sand, it seems to blend in almost as though it was hiding.

But it is not just that it is difficult to see or identify—that fused piece of sand is often very fragile.

How it is formed is what makes it so intricate—the interior often looks like a delicate, small glass cave— and so delicate.

For one incredibly brief moment when lighting strikes the sand the air can actually be hotter than the sun. Silica, the ingredient that gives the Outer Banks sand its soft, fine feel, immediately melts and fuses into a rock-like substance. As it cools beneath the surface the silica continues to melt and reform.

The outside of the fulgurite is hardened, but extreme heat is so great that it vaporizes the sand inside, hollowing out the interior of the fulgurite. The melted sand on the outside tends to be thin and very fragile.

Interestingly there are two places on the Outer Banks where fulgurite tends to occur and the it is slightly different at the two locations.

The sand on Jockey’s Ridge is finer and does not have the shell material found on the beach. The fulgurite formed at the park tends to look almost like the tip of a lightning bolt and has a cleaner, smoother surface.

Fulgurite formed on the beach will often have shells encased in the exterior and if the lightning strikes wet or damp sand, the shape will be altered dramatically.

There are two places on the Outer Banks that have fulgurite collections. The collection that Jockey’s Ridge State Park has is small, but some excellent examples

The Outer Banks Beachcomber Museum on the Beach Road in Nags Head has a remarkable collection of beach fulgurite.

Our Joe Lamb Jr., & Associates. beachfront homes are perfect for beach combing.