Very interesting WWII Ostland Eisen revenue trade chits. These were used in Germany as well as eastern occupied areas such as Russia, Poland, Western Ukraine and were used as an exchange chit for trading agricultural goods for steel or iron. I do not know the particular details but that is the gist. There a couple of different watermarks and one that was glued on something along the way. They look to be very nonchalantly cut but the basic size is 4x6cm. Very cool looking and interesting pieces.