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 bullion sizes based on the troy ounce, but some are "metric", like twenty-five grams (25g) of silver.
This coin is part of the History of the Crusades series and is dedicated to The Seventh Crusade and King Louis IX of France.
The Mint says about it:
The Crusades were a series of religiously sanctioned military campaigns waged by much of Latin Christian Europe, particularly the Franks of France and the Holy Roman Empire during the 11th to 15th century. Each coin depicts a unique scene from that crusade and the most important commander/leader in that crusade.
The Seventh Crusade was a crusade led by Louis IX of France from 1248 to 1254. Approximately 800,000 bezants (large gold coins of the time) were paid in ransom for King Louis who, along with thousands of his troops, were defeated and captured by the Egyptian army led by the Ayyubid Sultan Turanshah supported by the Bahariyya Mamluks led by Faris ad-Din Aktai, Baibars al-Bunduqdari, Qutuz, Aybak and Qalawun. | 
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