I have a round piece of lava I found not far from the Rio. on a sandy spot where I have picked pottery. will try to locate it for a pic. so round it rolls very nice
I have several Almandine garnets from a local mine and one is round and textured just like that. I have it at work for decor but will try to take a pic for comparison. Almandine garnets have been known to wash up in some of the creeks around here too.