Looks to me like a Hyderabadi gold.....I'm not sure though. The obverse insignia looks exactly like that of the Hyderabadi coins.
It looks like this (what Acanthite said): http://www.coinarchives.com/w/lotviewer.php?LotID=592576&AucID=431&Lot=1358 The price it sold for is there too but it appears to be in a little better condition so you can expect yours to be worth a little less. Ribbit
Gold will develop "green gunk" on it and I believe it's caused from the copper content but not sure. Several of my tiny California Gold Tokens had a little on them and I just dipped them in a capful of Tarn-X and it disappeared, with no traces of it left. hya: Ribbit
well if you are calling yourself stupid i hAVE no problems with that BUT the guess was quite intelligent. The hyderabadi coins were modelled after the ottoman and turkey coins