also put a magnet to it; a lot of Chinese fakes are made of steel (I don't know about fake gold coins, but they sell a lot of fake silver).

Always beware: there was an eBay seller in China who offered replicas of rare coins for only a couple dollars each, and he also offered to have them stamped as copies as U.S. law provides, or have it omitted since U.S. law does not apply to overseas sellers.