Hi,
I randomly got a full set of flyers from the German Münzgesellschaft for the 5DM coins. Starting from the 1979 Otto Hahn coin, they all describe the coins as copper-nickel - as they should - except for the one for this coin. That one describes a silver coin. I am not aware of this coin existing in silver, but you'd think the Deutsche Münzgesellschaft would get their facts right…
Cheers,
53th0s