Lightning turns sand to glass

Finding fossilized lightning in Florida

LAKE WALES, Fla – Take a look at these amazing glass fossils right here in Florida formed during lightning strikes.

Florida’s is struck by lightning more than any state in the U.S. and when the bolt hits soil a new rock called a fulgurite traces a fossilized path deep into into the ground.

The channel of heat in a bolt can reach temperatures hotter than the sun vaporizing sand and melting its outer edges. Within an instant the sand cools forming a hollow glass tube that can extend down to the water table.

Nowhere else in Florida does heat and pressure change minerals into something new called metamorphic rocks.

This makes collecting fulgurites interesting because they are elusive, unless you know where to look.

Meteorologist Mark Collins excavated hollow glass tubes in sand pit mines located along the Lake Wales Ridge in central Florida.

Forests are not the best locations but barren sandy areas are hotspots for fulgurite formation especially around central Florida sand hills that have been exposed to lightning for millions of years.

Wide fulgurite tubes directly correlate with bolts packing more energy according to research by USF Geologist Matthew Pasek, who estimates 10 fulgurites form globally per second. 

A hollow rock tube called a fulgurite formed when lightning struck sand, vaporizing it and melted its outer edges into glass.

Florida's sandy pit mines increase the likelihood of finding well preserved fulgurites compared to beaches. But many of these fossils are brittle and the nearly 100% homogenous quartz located in the pits reduces branching patterns more commonly found in fulgurites in western states.


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