fulgurite-close-up (IMAGE) University of South Florida Caption Close up of a fulgurite, a rock formed by an electric discharge that passes through nearby rock, soil and sand. Fulgurites are also known as ‘fossilized lightning.’ Credit Matthew Pasek/University of South Florida Usage Restrictions NA License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.