Unknown Old Coin

Wow that is a corroded coin! Based on the thickness alone, I would say your best starting point would be either Indian or Islamic of the early modern era. There are quite a few examples from the "Princely States" of India that pop up here on a weekly basis. We have a few experts in those coins, so I will defer any attempt to ID to them.

If it is not Indian, I would hazard to guess that this may be a token or similar. Again, too much detail is lost to the corrosion to make out anything to Google for a match.