'Pawn Stars:' Why a rare coin worth six figures sold for much less

On History Channel's hit show "Pawn Stars," a man came in to sell a 1907 Saint-Gaudens double eagle $20 gold coin. The coins are extremely rare, and some of them have sold for more than $1 million in the past.

The coin is 90 percent gold, 10 percent copper -- it's so rare, it's often faked. So, what about this particular coin?

"We could fetch anywhere between $17-18,000," an expert said.

"To me that seems awful low," said the seller.

Yes, an expert found something wrong with the coin: It had been cleaned.

"If this thing wasn't cleaned we'd be talking six figures," said the expert.

Shop owner Rick Harrison still ended up buying it for $12,500 -- that's well over the $1,200 value of the gold in the coin.

The Saint-Gaudens piece was the brainchild of Theodore Roosevelt who thought U.S. coins could be more beautiful -- an expert called these "one of the greatest coins ever made."

The Numismatic Guaranty Corporation, or NGC, verifies coins and says of these, "What's the most beautiful U.S. coin ever made? ... one of the first and most frequent answers is sure to be the Saint-Gaudens..."

If you want to get your hands on a coin like this, well, you have a few options ...

Both eBay and APMEX are currently offering those same coins - though they're in noticeably worse condition, and valued between $1,288.77 and $3,995.00.

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