Well, there's a $10 word and I am glad you mentioned it. Long ago I found an object in a big collection of marbles I purchased - honestly, it sort of gave me the heebie-jeebies, and I wondered for years what it might be. I eventually came around to thinking it might be a bezoar, but since it creeped me out so much I stuck it away somewhere and havent thought about it for about 15-20 years. Now I want to see if I can find it but I'm not sure it would be an appropriate post in the ID section - even though it has an interesting pattern and colors. lol