Aureus Magnus II Ducat Silver Medal Help Needed (Id: Reproduction Of Private Currency Medal)

One problem when you produce your own private currency, is this: there's not much legal recourse for you to take if other people start making lookalikes. They're not "counterfeits", since yours aren't "real coins" to begin with either, so the authorities would see it as a lower priority than somebody selling counterfeit money. The best you could hope for was charging them with some kind of copyright or trademark violation, assuming you could catch them.

In the Aureus Magnus series, "ducats" were gold; the silver coins were denominated in "argenteus" and didn't have the word "ducat" on them. The Nefertiti coins also all have the date in the space behind Nefertiti's headgear, and Werner Graul's WG monogram in the space in front, both of which are absent from your piece. So I think it's safe to conclude this is a copy; I would be surprised if it were solid silver.