Niue, a sovereign state in free association with New Zealand, uses two official legal tender currencies. The New Zealand Dollar is the circulation currency for daily transactions, while the government also authorises legal tender coins in the Niue Dollar currency for collector's purposes.
A number of mints issue a large variety of commemorative, bullion and collector coins under the authority of Niue. These coins are dedicated to historical or general popular culture themes not related to Niue itself. Many of them are in standard bullion sizes - typically, one ounce of silver (abbreviated as 1 oz Ag, where "Ag" comes from the Latin word for silver, Argentum). Many of these feature characters and themes from popular culture.
This coin is part of the Harry Potter Magical Creatures series, and features a Hungarian Horntail Dragon.
The mint says about it:
Harry Potter is a series of seven fantasy novels by J.K. Rowling following the life of young wizard Harry and his friends as they navigate the wizarding world and the rising evil of Lord Voldemort. Crucial to the plot of the series are the magical creatures who aid Harry in his journey.
Considered to be one of the most dangerous species of dragon, the Hungarian Horntail is an iconic creature in the Harry Potter series and is known for its vicious attitude and intimidating appearance. After drawing the short straw in the Triwizard Tournament in the fourth book Harry Potter and the Goblet of Fire, Harry faces off with one of these menacing creatures in a challenge to win the tournament. | 
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