Fulgurite

Fulgurite is a natural rock formed when lightning strikes sand or silicon-containing soil. The intense heat generated, which can exceed 1,800 °C, melts the surrounding materials and creates tubular or branched structures as it hardens. This fulgurite exhibits typical textures and cavitations where the sand has been vitrified. Fulgurites are generally found in sandy regions and can vary in size and shape.

The stones measure approximately 5 cm.