@fini75, well that is a good question. At the moment, I don't see any of these for sale online, but it isn't my impression that they are particularly rare. Normally, you could see what other folks are selling theirs for and then formulate a plan to be somewhere in that range. As far as I know, there are no price books for these medieval coins as there are for world coins starting in 1601 (the Krause catalogs and others).
Here is how I would value your coin: in 1977, a lot of 8 pieces was listed for sale in the auction catalog covering Dr. Friedrich Bonhoff's collection. The estimated total price was 100 DM, or 8.33 DM per piece. Looking at historical conversion rates and inflation, you are talking about a price of about $14.50 now. That said, there are multiple limitations to this calculation including the obvious facts that the coins may have sold for more or less than the auction estimate and their value may have gone up faster or slower than inflation. I would use 15 bucks as a starting point.
Perhaps some others on CCF have a different opinion?
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