This one, unlike the other two you posted, is not ancient. It appears to be a fake Spanish cob from the 16th or 17th century. I say "fake" because it looks cast, like many of the tourist souvenirs you can buy in museums in places like Florida. But since the original coins were so crude, it's hard for me to say 100%. Let's just say it looks suspicious. Someone who knows more about cobs may weigh in.
Because they're so crude, a lot of the real ones look fake. Guess that one could be OK. Like I mentioned, I really don't know for sure.
According to the label, your coin has a very clear and traceable provenance. It was found underwater in 1985 from the wreck of the Spanish ship Nuestra Senora da Atocha (sank 1622). Minted in Potosi. It has even an individual reference number : 85A-114449, which could easily be verified. I don't know if fake cobs come with fake identification labels too, but it seems there is no obvious reason to suspect your coin. Very nice !
