Funny Weird Agate Specimens You Should See
A Thunder Egg “Thunderegg” is a nodule-like rock, similar to a filled geode, that is formed within rhyolitic volcanic ash layers. Thundereggs are rough spheres, most about the size of a baseball—though they can range from less than an inch to over a meter across.
Thundereggs are nodular rhyolitic formations which can have hollow cavities and can contain a star, triangle, or lens shaped interior. These can fill wi...