Ok just answered my own question, found your other post in the finds section asking about the bell, I was thinking bell but like you said have never seen one like that before. Gotta love finding the oddities.
Nice finds! Ya know,I always fing my best finds within 20 to 30 minutes, after that I either stop paying attention or just don't find much.. Congrats on the coins!
I have dug quite a few of those threaded nut looking things in my pic... turns out they are part of the model T valve stem, which I just found out about. I have found numerous model T hub covers and these valve stem parts but haven't dug a valve stem cap yet... I know they are out there!