What is Fulgurite?

Published on Sunday, November 25, 2012 by Katherine

Angry Rock is with us at every meal at the beach house. He sits on the deck picnic table either holding napkins or simply enjoying our conversation. Sometimes we make up reasons why he seems so angry. “He’s angry because he can’t eat any crab,” or “He’s angry because he doesn’t have arms to feed himself.”

We have always picked up beach objects that look like Angry Rock. They are hard and appear to be made of compressed sand, often shaped like tubes or swirly blobs. For 30 years we wondered what these rocks were. That is, until this summer when I saw one labeled at the Outer Banks Center for Wildlife Education. Finally we knew what these big sand-like rocks were. Fulgurite!

Fulgurite is made when lightening strikes the sand or soil. The lightening hits the beach at 50,000 degrees and instantly melts the sand. Fulgurite is the result, showing the exact path the lightening took as it hit the ground. We often see shells and rocks melded in to the fulgurite pieces, making them even more interesting.

Some people call fulgurite “petrified lightening.” The fulgurite we find in the Outer Banks can be anywhere from a few days old to millions of years old. I am always intrigued by the pieces I find, noting the shape the lightening took when it hit and the shells that were caught in its path.

I often see faces of people or animals in fulgurite. Each one is unique and absolutely fascinating. Imagine holding petrified lightening. You can practically feel its energy in your hand!