Copper and black enamel art nouveau brooch

I bought this brooch a while ago. Its copper and black enamel and as you can see it has a c-clasp. I like its flowery decorations on the front and it seems art nouveau'ish to me, so my guess would be its made in the first half of the 20th century. Its not high end, but when you look at the back it looks very crudely made, with parts of the copper not evenly spread.
So, is it old or could it be a remake?
Thanks a lot!