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. Many of them are in standard sizes, including the half gram (0.5 g) of gold mini-coin format - such as this coin.
The mint says about this coin:
The Matterhorn is certainly one of the most famous mountains in the world. With its nearly perfect symmetrical pyramidal peak, it defines what many consider a true mountain. It is both awe-inspiring and intimidating to even the most skilled mountaineers and has taken the lives of well over 500 climbers making it also one of the deadliest mountains to climb. It extends 4,478m above sea level and is one of the highest summits in the Alps and Europe. It wasn’t conquered until 1865 when Edward Whymper and 6 other men beat out an Italian group of climbers to reach the summit. Whymper noted down: “At 1.40 p.m. the world was at our feet, and the Matterhorn was conquered. Hurrah! Not a footstep could be seen.” Precisely at this moment the Italian team was approximately 400 meters below, still dealing with the most difficult parts of the Italian ridge. When seeing their rivals on the summit they gave up on their attempt and went back home. 4 of the 6 Whymper’s team members lost their lives on the descent. All but one (whose body was never found) are buried in the Zermatt churchyard.
This coin and the 2 oz silver version (to which it is a "companion" edition), are struck to capture the majesty and awe that the Matterhorn gives. | 
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