I wasnt intending to be mean...but if you say the person who sold it to you said it was real, they have a reason to be dishonest because they will make money. If you took it to another jewler they have no reason to lie to you because you already own it
contrary to luckyass's statement, a magnet will not prove a item is gold. a magnet will however prove an item is not gold. if magnet does not stick it means it is not ferrous (iron), but is still could be brass for instance, instead of gold. a magnet is helpful, but no guarantee.
oh and since u said u won't refund the winners credits if they take it an find out it's not really gold can u at least send the receipt from whenever u bought it and how much did u pay for it cause it'll help us with knowing before bidding cause whenever someone won't guarantee it well seems like somethings not right amd with u getting as much credit as u have right now thts not good to lose that much for something that is not worth 10 dollars so ya can u do that at least