Numismatic Guaranty Company® (NGC®) is the world's leading authority on mint errors, a popular segment of numismatics. In Mint Error Coin Chronicles, we take an in-depth look at these mistakes on coins.

NGC recently certified the L. E. Bruun Collection, a stunning group of thousands of Scandinavian coins that is being offered in a series of auctions presented by Stack's Bowers Galleries. With that sheer number of coins, there were bound to be a few mistakes, and here are a few of them (being offered in a February 2025 auction) that involve the design of the coins, with the errors engraved into the dies themselves.

This Denmark 1704 Gluckstadt 8 Skilling graded NGC MS 63 was struck during the reign of King Frederik IV, who ruled from 1699 to 1730. On the obverse, the number IV in the king's name was mistakenly rendered as VI. King Frederik VI, a great-great-grandson of King Frederik IV, ruled a century later.

This Denmark 1771KM Skilling - DANKSE graded NGC VF 35 BN has the word DANKSE instead of the expected DANSKE, the Danish word for Danish.

A similar error occurs on this Denmark 1789 MF Schleswig-Holstein 20 Schillings graded NGC F 12. At 1 o'clock on the obverse, the expected DAN that indicates that Christian VII is king of the Danes was instead rendered as DAV.

This Denmark 1787 MF Schleswig-Holstein 40 Schillings graded NGC Fine Details has a spelling error on the reverse, where the word COURANT is missing its U. The word courant, which was used to describe the currency in Schleswig-Holstein, is spelled correctly on the reverse of the previous coin.

Finally, this Denmark 1838 IC//SW Speciedaler graded NGC AU 53 has an error involving the initials of the mintmaster. On the reverse, surrounding the date, they are rendered as SW, instead of the expected WS.