America is braced for a nationwide treasure hunt as the Philadelphia mint confirmed it had made a mistake when minting some of a new batch of dollar coins.

The coins were supposed to have the traditional "E Pluribus Unum" inscription, along with "In God We Trust" around the edges. But due to an unholy error, both inscriptions were left off. The mint was not able to say how many of the 300 million coins the error had affected, but issued a statement saying that it was taking the necessary steps to correct the defect.

"We also consider quality control a high priority. We are looking into the matter to determine a possible cause in the manufacturing process."

Coins with minting errors are always collectable, particularly when the run with the error is only small.

According to Reuters, one of the uninscribed coins has already sold on eBay for $405. Although that is already a nice return on the initial dollar "investment", hanging on to it for a while could pay huge dividends.

In 1922 a mistake in the minting process meant a number of one cent pieces were issued without a "D" for the Denver Mint they were stamped at. One of these coins would sell today for up to $10,000, according to Robert Hoge, curator at the Numismatic Society. ®

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