Rare druzy Australian thunder egg

Half Rare druzy thunder egg found in Morella Australia with smoky quartz inclusions

6.8cm
95g

A thunderegg (or thunder egg) is a nodule-like rock, similar to a filled geode, that is formed within rhyolitic volcanic ash layers.

Formation:

Volcanic rock like rhyolite, rich in silica, can sometimes trap gas bubbles as it cools. These bubbles expand and create hollow spaces. Over time, minerals like silica and feldspar crystallize around these cavities, sometimes forming radiating crystal fans. The result? Spherical objects called thunder eggs.