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 - including this very large five ounces of silver format (abbreviated as 5 oz Ag, where "Ag" comes from the Latin word for silver, Argentum).
This coin is part of the first issue of New Zealand Mint's Marvel Classics series featuring characters from Marvel comics, and the Shield of Captain America.
Captain America is one of the most famous and popular superheroes of the Marvel Cinematic Universe. The character was originally developed by creators Joe Simon and Jack Kirby and was first introduced in the comics in 1941. Captain America, also known as Steve Rogers, is a former soldier in World War II who became an invincible fighter through an experimental super-soldier serum. After the war, the superhero was frozen and only found and unfrozen decades later. He joined the Avengers as one of the founding members in order to continue his mission to defend the world from evil.
The mint says about the coin:
This large 5oz pure silver coin, with an impressive 75mm diameter, does justice to Captain America’s one and only weapon, his Shield! The round coin has a concave back, pushing the image outward. The design is mostly in colour but the star and one of the circles have been left engraved and frosted. On the obverse is the Public Seal of Niue, confirming the coin as legal tender.
A high-quality box, lined with velvet, encases this spectacular piece. Inside is a separate Certificate of Authenticity, that includes the coin’s unique number in the limited mintage of just 500 coins. The vibrant, themed outer box features imagery of the hero himself. | 
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