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).
Downies says about this coin:
The 2024 $10 Creatures of the Abyss 5oz Silver Proof is a groundbreaking coin that takes a dive into the very latest minting techniques to reveal the secrets of the ocean’s darkest depths.
Boasting an impressive five ounces of pure 99.9% silver, the 65mm reverse is a window into an underwater abyss. The anglerfish’s bioluminescent illicium, or rod, illuminates the terrifying denizens of the deep, including the lanternfish, fangtooth, viperfish and hatchet fish. These species exist within the gloomy bathypelagic zone of the oceans, between 300 and 1,500 meters. At this depth, there is no light and the water is near freezing!
The spine-chilling effect of the coin’s design is achieved by the clever use of deep black gradient Digital Colour, which allows the detailed features of these mysterious creatures to emerge from the darkness in a spectacularly realistic manner. | 
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