It is 90% gold, 3/4” wide and weighs 3.36 grams. I know what it represents, Mozart’s opera The Magic Flute. I could never find out any history behind it.
Here's a link. I found one other site that had essentially the same information. https://www.auktionshaus-stahl.de/en/article/108235-a-gold-medal-mozart Yours seems to be a smaller version than the one in this listing. I have seen some precious metals medals like this from Europe come in different sizes while keeping the same design. It doesn't seem to be an official government issue, so most of its value will lie in the precious metals weight, possibly a small premium for the subject matter.
