When I'm fossil hunting, I generally bring home mystery items that I can't explain since I know they are something. I was talking geology/paleontology shop with a fellow rock hound when I showed him some mystery structures I found in the Miocene bone bed that were unlike anything I've seen. Structures were very crystalized and glass-like with fossil shark teeth attached via outside matrix. He said they were most likely Fulgurites. Fossilized lightning bolts! I will seek further confirmation from another geology source to confirm, but it would make sense since I've found nothing remotely similar here over the past few decades.
Very cool phenomena.
Ironically, they could from the present day or in this case an ancient lightning bolt from 15 million years ago since it was deep in the bone bed (Surface back then)
(https://i.imgur.com/Ir1BCw7.jpg)
(https://i.imgur.com/83WE6SE.jpg)
They come in all shapes and sizes depending on where they hit and what type of substrate they impact.
https://www.google.com/search?q=fulgurites&rlz=1C1GCEA_enUS834US834&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiLu-rjyJ_0AhWPGDQIHeKxAQ4Q_AUoAXoECAEQAw&biw=1536&bih=775&dpr=1.25
You definitely have an eye for that stuff, amazing things that Mother Nature creates is pretty interesting 8)