Unknown Medieval Coin With Griffon And Crown-Identification Help Requested

I think it says GROSSI PRAGENSES around the lion and DEI GRATIA REX BOEMIE on the other side. I suppose the inner legend would have the ruler's name WINCEZLAVS... (or something similar). It would mean it's a Bohemian coin.

And here's what might be the second word in the inner circle around the crown: TERCIVS (the third).

Compare the position of visible letters on your specimen with this old e-bay image which I enlarged:

Coin forum, many thanks! I need to brush up on my medieval lettering.

I apologize, I guess that is a lion not a griffon.

Differences in counting usually arise from differences between actual history and official history. In this case, the king we now call Wenceslaus III was the uncrowned son of Wenceslaus II, who ruled Bohemia for just over one year before being assassinated. He apparently either issued no coins, or issued coins only in the name of his late father. When the king we call Wencesalus IV came to power sixty years later, he seems to have conveniently forgotten (or perhaps even been unaware) that the previous Wenceslaus III had ever existed.

Too unimportant to count at the time, but later history is more generous. Makes sense.

Well, being royal was rough in those days, but they had real power if they could grab it.