Offa was right, it's this coin: https://www.acsearch.info/search.html?id=289398
Here is the Numista page and another source:
https://en.numista.com/catalogue/pieces108582.html
https://katzauction.com/lot/331527
Yes, it is a Henry II Denier, made sometime between 985 and 995, no way to tell when as the coin has no date. That's a nice find!
It was made for the Duchy of Bavaria, which was one of the many German states.
The coin was auctioned by Katz for about $190.
Hope this helps!