Fulgurite Petrified Lightning 5 Pieces Raw Minerals Stones Rocks Collecting

Lot 5 Pieces Fulgurite or Petrified Lightning 11.4 gr - mm 20-34 Raw Minerals Stones Rocks for Collection, as in photo.
Also available in single selected pieces, at this link.

The Fulgurite (from the Latin Fulgur = lightning) is a glassy mass, tubular in shape and hollow inside, produced by the energy released by lightning on a sandy soil rich in quartz.
The heat generated by the electric discharge melts the silica sand containing quartz and giving rise to fulgurite. The resulting glassy mass called lechatelierite, is amorphous and usually classified as mineraloid. The lechatelierite can form more rarely also in response to other events such as the impact meteor or volcanic explosions, in which the temperatures developed are sufficiently high to melt the silica.
A fulgurite has a typical diameter which can vary from a few millimeters to a few centimeters and a length ranging from a few centimeters to a few meters. The generally typical greyish color of the fulgurite is due to the numerous impurities present in the sand and which are embedded within the glass.
A fulgurite is also called petrified lightning, as it looks like the imprint of lightning on the ground.
Since the lightning develops a very high temperature, profoundly alters the molecular state, giving rise to the formation of new minerals following a rearrangement of the constituent molecules hit the mineral. The sand containing quartz (SiO2) easily undergoes this alteration.
Occasionally a fulgurite can form a vitrified layer on the surface of a rock based on quartz. In this case it is also called fulgurite esogenica.
The fulgurites find is an extremely rare event, since it is extremely fragile objects and thus poorly preservable in nature. One of the largest was found in South Amboy, in the state of New Jersey in the US. It was a little more than 270 cm long and with a diameter of 7.6 cm in the part towards the surface of the ground; the tip then thinned up to 5 mm at the deepest point. As often happens with the fragile nature of fulgurites, scholars were not able to pull it out whole and the largest fragment was recovered along just 15.2 cm.
They have frequent finds on Mount Thielsen, Oregon, that because of the frequency of the lightning that strike is called the lightning rod of the Cascade Range. Here you fulgurites take the form of a glass layer greenish-brown on the surface of the rocks.
The largest preserved fulgurite integrates is located at the Peabody Museum of Natural History at Yale University: comes from the shores of Lake Congammond in Connecticut and is 4 meters long. Another outstanding fulgurite that complex is 3 meters long is exposed to the Natural History Museum in London; It is however kept in long clips 50 cm.