Fossilized Mudstone

You heard it right, this is a geode of fossilized mud! The unique pattern is caused by minerals and agate that gets trapped between the cracks of mud. Mudstone is a sedimentary rock formed from fine-grained particles of mud or clay that have been compacted and lithified over millions of years. It typically contains a high proportion of clay minerals, along with varying amounts of silt and organic matter. Fossilized mud often preserves a wealth of information about past environments, including clues about ancient climates, ecosystems, and geological processes.