Pretty sure that is a solidus from Poland (Johann Casimir). Don't have the Krause book in front of me right now...
I think Lithuania KM-50. It's listed under schilling, but solidus and schilling I think mean the same thing in Poland. On the obverse, it should have TLB or GFH under the portrait. There was listed a 1664 GFH and 1664 TLB/HKPL in my 17th century Krause. Found this in Numista: https://en.numista.com/catalogue/pieces119356.html
I believe KM50 is right. I think 1661 TLB. I think it's interesting that Krause gives a total mintage of 7,000 for 5 years of this type (with TLB) ... not many mintage figures from that era... So the Polish king on the obverse and a Lithuanian hero, Vytautas, on the reverse. Thanks guys!
So here is the correct Numista entry ... for 1661: https://en.numista.com/catalogue/pieces119349.html
