Feathery Plume Agate Mass from the Almus Dam Bed, Tokat, Turkey
We are no longer VERY adjacent, I will admit, but once you start exploring the whole world of agate structures tangled up in other materials - blobs of stuff surrounded by other stuff - it is hard to stop. This is most emphatically not a thunderegg mass in any way - but it is an amazing specimen of plume agate with some unusual structures.