Stamp of Maastricht with number 0
From 1915 onwards, it was customary to include a serial number in new date stamps. This was convenient for administration, but it also served as a means of verifying the service performance of a postal employee. By examining the impression of the stamp on the postal item, for example in the event of complaints, the serial number and date allowed one to determine who had applied the stamp impression.
In 1917, a stamp with serial number 10 was issued. This stamp contained the letters V (before noon) and N (afternoon) as hour indicators. This stamp was modified in 1939, whereby the hour characters were replaced by so-called 24-hour characters (1-24 hours). The stamp went missing in early May 1949. This was confirmed in a letter from the director of the Maastricht post office, written on May 27, 1949, to the Director General of Post in The Hague. Consequently, a new stamp was ordered.
The stamp was ready quickly, for as early as May 30, 1949, a new copy, supplied by De Munt in Utrecht, was sent to Maastricht. With serial number 10. But that was not the intention! It was customary for a new stamp with an unused serial number to be issued in the event of missing stamps. This was due to the possibility that the lost stamp might fall into the wrong hands, enabling 'fraudulent activities' to take place.
The stamp was returned to The Hague. Apparently, it was considered a waste to destroy a brand-new stamp, and an official from the technical department who got his hands on the stamp had an idea. He removed the digit 1 from the serial number 10, leaving the digit 0! This satisfied the requirement that a replacement stamp had to have a serial number that had not been used before.
The stamp with serial number 0 was accepted and returned to Maastricht on June 13, 1949. Consequently, impressions of this stamp can be found on postage stamps and postal items. The stamp was taken out of service and destroyed at the end of 1969. It was not until March 20, 1973, that a new stamp with serial number 10, of an entirely new model, was issued. Confusion with the missing stamp was not possible.
Stamp impressions, you can have quite an experience with them, can't you?

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