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 Tenth Crusade and The Last Crusader.
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 Tenth Crusade is also called the Alexandrian Crusade. The brief Alexandrian Crusade, also called the sack of Alexandria, occurred in October 1365 and was led by Peter I of Cyprus against Alexandria in Egypt. Relatively devoid of religious impetus, it differs from the more prominent Crusades in that it seems to have been motivated largely by economic interests.
After the Tenth Crusade, there were just some minor crusades left as the spirit of crusading was finished. Increasing Muslim victories and Christian defeats led to the end of the Crusades. | 
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