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 famous movie characters.
This coin is part of a New Zealand Mint series dedicated to famous movies in the form of their original posters, and features Harry Potter and The Sorcerer's Stone.
The Mint says about it:
"Savour a piece of movie history with this officially licensed Harry Potter and the Sorcerer’s Stone replica movie poster coin made from 99.9% pure silver. Celebrating the first film in the Harry Potter series, this unique rectangular coin uses both colour and engraving to showcase the iconic poster.
This treasured 1oz silver collectible arrives in an innovative perspex holder which frames the coin and allows for easy display. A uniquely numbered Certificate of Authenticity sits within the packaging, which is also Harry Potter branded to complete the aesthetic." | 
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