Posted this on another forum and people got a good laugh out of it, so thought I'd share here as well. http://www.ebay.com/itm/West-Indies-Guadeloupe-Crowned-G-Countermark-Counterstamp-British-Colonial-/221393324092?pt=US_World_Coins&hash=item338c12083c&nma=true&si=RROJpvg2VF2kgdqu3l2vCpS%2F%2BhE%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557 The coin is cast with the countermark already on it, rather than a punched c/m on a previously struck coin. It's possible this is a contemporary piece, but I'm leaning towards modern.
It's not fairly modern. There are a bunch of dirt and other particles in the devices, so it's been around a while. There is also wear on high points of a different color, which appear with age and use as well.
All of these things can be the result of the casting process, especially when a sand mold is used, as appears to be the case here. Check out the roughness around the top of the reverse and crown, sure looks like a candidate for a sand or sand and clay mold to me.
I'm with Detecto on this one. I think what may account for the unusual diagnostics of the coin is that it may well have been in the ocean. It could be a shipwreck piece.
If that is all you have to say to conclude the above coin is not from the ocean then I believe it may still have come from the ocean. I have seen quite a few silver coins that were submerged in ocean waters which were in remarkably preserved condition. There are various factors which affect silver coins in the ocean. These include pH and salinity levels of the geographic location of where coins rest, whether they settled into the mud of the ocean floor, whether the coins remained stationary and didn't move, whether they were disrupted by ocean currents and storms, and the length of time they were in the water before being recovered.
Take a minute to bring this coin up with people familiar with shipwreck coins. It will be a learning experience, something that every single one of us have at one point or another.
