The Professional Coin Grading Service grades this 1998 American Eagle silver bullion coin struck on a planchet intended for a commemorative silver dollar as Mint State 68. It has traded privately twice at least, the second time at $50,000. More pieces like this may be hiding in investors' unsearched monster boxes of American Eagle silver bullion coins.

This 1998 American Eagle silver bullion coin, struck on a planchet intended for a commemorative silver dollar, is slightly smaller in diameter and lighter in weight than a normal bullion coin. It also has plain edges, since it was not big enough to spread to meet the edge die that would have formed reeding on a normal-sized American Eagle silver dollar planchet.

This 1998 American Eagle silver bullion coin is struck on a planchet intended for a commemorative silver dollar. The commemorative planchet is slightly smaller in diameter and lighter in weight than those intended for bullion coins.

A series of coins where it is extremely rare to find major errors is the American Eagle silver bullion coin series.

In 2013, a unique wrong planchet error 1998 silver American Eagle, struck on a commemorative silver dollar blank, was discovered and sold to a collector on the West Coast. Since I had a customer who was interested in the coin, I did some research and was able to track it down, purchase it, and subsequently sell it to him for $50,000. While this is a high price for any error, the coin is the only known wrong planchet error for the entire silver American Eagle series, making it a highly desirable coin and something that any serious collector would love to own.

The previous owner of the coin loved it but was liquidating some coins, so this coin became available for purchase by the current happy owner. Although I do not know how the coin was originally found, it was doubtless found mixed in with other 1998 silver American Eagles, by some lucky collector or dealer who noticed the coin’s not having a reeded edge, and also its slightly smaller diameter. It would have really stood out among other silver American Eagles.

Whoever found the coin originally made an incredible cherrypick, and certainly a large profit! At a glance, the coin appears to be the same as a normal silver American Eagle, since it is silver and nearly the same diameter as a normal coin, but it is in fact very different. A normal silver American Eagle weighs 31.1 grams, which is a troy ounce of silver, and has a diameter of 40.6 millimeters. The planchet this 1998 silver American Eagle was struck on weighs 26.73 grams and measures 38.1 millimeters, which are the specifications for a commemorative silver dollar planchet.

Another big difference is that there is no reeding on the coin’s edge, which is because the collar die could not make contact with the planchet’s edge due to the commemorative planchet being a smaller diameter than a silver American Eagle planchet. Also, the coin is triple-struck, although it is not noted on the Professional Coin Grading Service holder’s insert. There are strong traces of tripled design elements, and there are “rings” around the rim on the obverse and reverse, which indicate multiple strikes in accordance with how many rings there are. This makes the coin that much more special.

How was a silver commemorative planchet able to make its way into a press striking silver American Eagles and get struck? In 1998, the West Point Mint and the San Francisco Mint were both striking American Eagles. The West Point Mint was at the same time striking commemorative silver dollars — the Black Revolutionary War Patriots silver dollar and the Robert F. Kennedy silver dollar. One of the silver dollar planchets for these coins must have accidentally become mixed in with a group of American Eagle silver planchets. It then was fed into the press striking the silver bullion coins and was struck into this coin.

Because it is similar to a normal silver American Eagle and weighs very nearly the same weight, it managed to pass the inspections and weighing processes, and was shipped out with the other silver American Eagles.

Are there more of these out there? Possibly.

Because the weight, metal, and diameter are very nearly the size of a normal silver American Eagle, it is entirely possible another of these is out there, possibly in some investor’s “monster box” of silver American Eagles. Because most investors aren’t going to get out and individually count their coins, probably millions and millions of coins in these boxes have not been searched yet, creating an opportunity for the cherrypicker. Hopefully some collector out there will find another!

Jon Sullivan is a member of the Combined Organizations of Error Collectors of America, Florida United Numismatists, American Numismatic Association, and other clubs. His firm, Sullivan Numismatics, focuses on error coins.