Did You Know? Fulgurites (from the Latin fulgur meaning thunderbolt) are natural hollow glass tubes formed in quartzose sand, silica, or soil by lightning strikes. They are formed when lightning with a temperature of at least 3,270 °F instantaneously melts silica on a conductive surface and fuses grains together; the fulgurite tube is the cooled product. This process occurs over a period of around one second. LEARN MORE.
