The coin that illustrates this story is a 1951 Norwegian 1 Kronor struck on a 1946 Swedish 1 Kronor. Is this a “true error” or what is it?
In 1951 a group of numismatists were invited to the Royal Norwegian Mint in Kongsberg. This was a formal visit arranged by Skanes Numimatiska Förening, a Swedish coin club located in the south of Sweden. As a friendly gesture to the visitors, the Mint placed some Swedish 1 Kronor coins in the Norwegian coin press and struck some 1 Kronor coins. Each person who wanted one of these was given one. Therefore, it may be wrong to describe the coin as a true error. To this day approximately 10 coins are known that were struck deliberately in this way. A few of these coins have been offered on the market and have been purchased by collectors.
40 years later I made a visit to the same Mint with a group of collectors from Gothenburg Numismatic Society. At that time I was not aware of the deliberate overstriking that had occured 40 years earlier. A few of the group-members noticed some unstruck planchets that were lying on the floor. The staff was alarmed at this discovery and even if I had known about the overstriking that took place in 1951, it probably would not have been a good idea to make a similar proposal...
In the picture above you can see that the Swedish legend surrounds the Norwegian King Hakon VII's symbol. Under the symbol you can see the head of the Swedish King Gustav V, who had passed away in 1951.