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 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 - such as a quarter ounce of gold (abbreviated as 1/4 oz Au, where "Au" comes from the Latin word for gold, Aurum). Many of these feature famous movie characters.
This coin is dedicated to Marvel character Iron Man.
The mint says about it:
Genius. Billionaire. Philanthropist. Tony Stark's confidence is only matched by his high-flying abilities as the hero called Iron Man.
Made of 1oz pure silver, this coin has been uniquely shaped and coloured to resemble the powerful Iron Man wearing his signature red armour and helmet. His chest RT has been left engraved and frosted for detail and some relief has been added for a 3D effect. Despite its shape, this is still a legal tender coin with the obverse displaying the Public Seal of Niue.
Officially licensed, the coin is tucked in a vibrantly coloured box, themed with imagery of the hero. Printed on the back is a Certificate of Authenticity and the coin’s unique number in the limited mintage of 5,000. | 
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