A "mule" error, as it is called, is when a obverse or reverse has a design that is not typically seen on the coin. A famous example is the 2000 Sacagawea and Quarter. It had a Sacagawea Dollar planchet and reverse struck on an obverse of a state quarter, and sold for a record price of $192,000! Mule coins are generally VERY rare, and attract a lot of attention when one is found. They have a very low chance of being produced, because it is unlikely a mint official will overlook something like that. There are only a few mule coins certified by a leading grading service. Keep in mind that minor, or 4th party grading services might certify fake coins due to lack of knowledge or as an attempt to gain publicity. The most famous example of a cent mule error is arguably the 1959 D with a wheat ears reverse. As you all know, the cent's reverse was changed in 1959 to the memorial style reverse. Somehow, a old die must have gotten mixed in and struck this piece. This piece is still a matter of discussion as to whether it is a mint product. It was discovered in change in 1986 by Leon Baller. He sent it in to the US treasury in 1987 for authentication. The letter he received stated that they had examined his coin, and that their opinion was that his coin was a genuine mint product. Despite this, NGC, PCGS, and ANACS all sent the coin back to him with a, no decision grade, unslabbed. J.P. Martin from IGC stated that, "He had no evidence to prove that the coin is fake, but his gut instinct told him that it was not a genuine mint product." PCGS founder David Hall also said that he thought it was fake. It does seem odd that there is only 1 of these coins produced. If a die had struck the coin, there probably would be more examples by now, 110 years after this piece was "minted." It was put up for auction in 2003 by Goldberg auctions. They graded it MS(60), but no major service had chosen to certify it. It was pulled from the auction when forager Mark Hofmann confessed to making the coin. It was put back for auction and sold for $48,300. It sold again in 2010 for $27,000. It was sold again in 2019, in September, and sold for $50,000, which was exactly the estimate. This coin is widely discussed in forums mostly anywhere, and is widely known. My opinion is that, this piece is a mint product, and was just struck by a mint official who wanted to make something interesting in his free time. Many people, however, think that it is fake. The general opinion is that this piece is fake, although if another example surfaced, it might change the opinions of many people. I hope you enjoyed this blog! My question for this blog is - Do you think that the 1959 D mule cent is genuine or fake? Happy hunting!