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 DC Comics characters and themes, and features the Aquaman Emblem.
The Mint says about it:
Celebrate the 80th anniversary of Aquaman with this 1oz pure silver coin. The coin has been shaped and coloured to resemble the emblem for Aquaman. The Ian Rank-Broadley effigy of Her Majesty Queen Elizabeth II features on the obverse along with the significant year of 2021 - which is 80 years since Aquaman first appearance in More Fun Comics #73.
Despite the unique shape, this is still a legal tender coin with a limited mintage of just 5,000. Inside the quality packaging, showing the matching emblem in gold colour, you will find a Certificate of Authenticity. | 
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