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 Flash Emblem.
The Mint says about it:
This 1oz pure silver coin celebrates the Scarlet Speedster, The Flash. The coin has been shaped and engraved with a bolt of lightning, the emblem for The Flash. This has been defined with yellow enamel to make it pop, while the mirror finish on the shield ensures it shines in the light!
The Ian Rank-Broadley effigy of Her Majesty Queen Elizabeth II features on the obverse and, despite this coin’s unique shape, confirms it as legal tender. This is a limited edition, with only 5,000 coins available worldwide. A unique serial number on the Certificate of Authenticity, placed inside the packaging, confirms each coin‘s number in the mintage. | 
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