In that case, if it's a silver coin, you are probably talking about losing $50 or less. On the gold coin, it's a common coin that should sell for about spot, so someone is already overpaying by about $500 based on Friday pricing.
People have done that with the coins they committed to buy from the U.S. Mint. Speculators would buy an issue thinking that it would able a good one they could flip easily for a profit. Then when the thing didn't take off, they canceled the order or returned the coins for a refund because they were "defective." BTW, once the U.S. Government artificially raised the gold price to $35 an ounce in the 1930s, it never went down to $25. The official price was $35 until Nixon raised it to $42 and something before Ford took the restrictions off on owning it.
Sure. In fact, if it was a single silver dime, they were out even less. But if it was $5000 worth of coin, whether that was a single AGE or a big stack of ASEs...