Special coins commemorating events in the reign of Queen Elizabeth II are normal for several major mints with current or past ties to the British Empire, which once spanned the globe. In 2015 there were two celebrations, one well known and one known mostly among coin collectors.
The reign of Queen Elizabeth II became the longest reign by any monarch of the United Kingdom, and going back in history it eclipsed the reigns of every English monarch before the United Kingdom even came about. Whether one is in favor of a monarchy or not this is indeed a major event, and has been newsworthy throughout the world.
The other event, one in a sense related to the long reign of Queen Elizabeth II, is that many major mints have once again changed the effigy used on coins of Queen Elizabeth II to the fifth effigy used during her reign.
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