the biggest one is 60 cm across and 15 cm deep

pyritic shales

This is a rare and fantastic 75

This beautiful Impact melt rock comes from the Stac Fada impact structure in Scotland

Fulgurite | Natural Lightning Impact Glass | 1.56 Grams | Sahara | SO24 Triphane the biggest one is 60Fulgurite, also known as fossilized lightning, are natural glass tubes or formations that are created by the heat of lightning strikes. When a lightning bolt hits the ground it generates temperatures of up to 30,000 Kelvin (over 53,000F), hotter than the surface of the sun. This intense heat melts the silica rich sand and fuses it almost instantly, forming hollow branching structures that solidify as they cool. In the Sahara Desert where thunderstorms