I believe that the bumpy surface is indicative of a modern reproduction. Also the style of writing looks odd. I think it's an imitation of a coin of Emperor Shih Tsu, aka Shun Chih, aka Shizo, 1644-1661.
Thank you very much for your info. A little history on my side re the coin: I have had this coin in my collection since +-1970 and when I searched for it in Krause's standard catalogue of world coins I noticed that there were quite a few coins that had a pimple planchet. I know in the past there have been replicas produced by companies but there is always a mark of some sought on the coin except for the 1700s English gambling tokens. I have searched the coin for tell tale signs of reproduction but can find none so for this reason I sought your expertise.
