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 movie characters. Some are also in innovative shapes, such as "Chibi".
Chibi (ちび or チビ) is a Japanese slang word describing something short (a thing, an animal or a person). The term is widely used to describe a specific style of caricature where characters are drawn in an exaggerated way: small and chubby, with stubby limbs and oversized heads. Coins of this type look like cartoon characters and have their corresponding shape; they are also very thick for their size.
This coin features The Joker from the Batman DC Comics Series.
The Mint says about it:
This limited-edition coin showcases criminal mastermind and possibly one of the most infamous DC Super-Villain in the DC Comics universe, The Joker. Made from 1oz pure silver, the coin is part of our officially licensed Chibi Coin DC Comics Series. Each is shaped and coloured to resemble the Chibi art version of The Joker, instantly recognisable by his trademark green hair and purple suit.
On the obverse of this wicked coin is the Ian Rank Broadley effigy of Her Majesty Queen Elizabeth II to confirm it as legal tender. The coin is kept safe inside a custom-made case, moulded to its unique shape. The Joker-themed outer box includes a large window to easily display Batman’s greatest foe without having to remove it from the packaging. Confirmation of the coin’s serial number also appears on the box along with a Certificate of Authenticity. | 
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