Fulgurite: A rare phenomenon

A bolt of lightning is able to deliver up to 5 gigajoule of energy (energy that can power a house in the US for over a month).

A bolt of lightning is able to deliver up to 5 gigajoule of energy (energy that can power a house in the US for over a month).When such a powerful lightning strikes a sandy area, then under special conditions, the sand particles can melt and fuse in less than a second. It is known that the sand melts at about 1,800 degrees Celsius, and the temperature of a bolt can reach 30,000 degrees Celsius.

So, sometimes when a bolt of lightning strikes sandy areas, tubes of sand that are called fulgurites are created. Despite the fact that there are over one million lightning that strike Earth every day, the fulgurites are rare.

Fulgurites are usually occurring beneath the surface of the sand and their shape reflects the way that makes lightning as it dispersed into the ground.

Fulgurites resemble roots with rough surface. However, the inner surface is smooth and glassy, because of the fact that the sand cools rapidly and solidifies. Their size is based on the strength of the lightning and the thickness of the sand bed. There are some occasions that fulgurites can penetrate deep into the soil, up to 15 meters below the surface.

The fulgurites are known since 1711 and they are appreciated for their scientific value. A fulgurite that is 250 million years old found in the Sahara, has confirmed that the desert was a fertile area where the storms were frequent.

Some people claim that this image is an example of fulgurite. In fact, it is a sculpture (wood from the beach that is covered with sand) creation of "Sandcastle Matt".

As the Museum of Hoaxes rightly observes, "A fulgurite of that size would be extremely valuable, and most likely would already have been carted away to a museum. It wouldn't be sitting on a beach surrounded by holiday-goers, any one of whom could potentially break it."