Very nice ancient coin! Interesting too. Looks to me like it has been in the water, perhaps the ocean for awhile. Don't know what kind of coin it is but one wild guess would be Arabic or Indian. Good luck on your search.
Hopefully someone can tell me what this is. I was given two of them and, given the marking on the reverse, I assume they are primarily silver. Any additional information will be welcomed!
The top pic doesn't fairly represent the colors - not sure what happened with the upload. Hopefully this one is better.
definer: Not a coin. A silver round. Value? Silver melt + or - a %'age But, you should start your own thread.