The Cook Islands, a sovereign state in free association with New Zealand, uses two official legal tender currencies. The New Zealand Dollar circulates in parallel with the local Cook Islands Dollar; at the same time, the government also authorises many legal tender coins in the Cook Islands Dollar currency for collector's purposes.
Collector coins are dedicated to historical or general popular culture themes not related to the country itself. Many of them are in standard bullion sizes, including the large three ounces of silver format - such as this coin.
The Mint says about this coin:
The "Poseidon: God of the sea" coin is the third issue in the award-winning "Gods of the World" series. The coin has an antique finish with dark highlights and is struck on a 3 oz pure .999 silver 50mm blank in the highest quality. It has a limited mintage of only 333 pcs worldwide and comes in a beautiful box with a Certificate of Authenticity. Get this 3rd edition now to complete your collection.
In Greek mythology, Poseidon was the God of water, sea, horses, and earthquakes. He was one of the Olympian gods and the brother of the supreme God Zeus. The name Poseidon has, unlike most other Gods, an Indo-European derivation. The God is known for his stiff character and the trident he always carries in his hand. He got this trident from the cyclops (one-eyed giants). The Roman equivalent of the deity is Neptune. | 
Search for Cook Islands: Silver Three Ounces 2019 Gods of the World - Poseidon on eBay 