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:
Vaults are an integral part of the building in which they are located, with armoured walls and a door secured with complex locks, they hold the items we find most precious. Historically, vaults were built in the basements of banks where the ceilings were vaulted, hence the name. Nowadays they are also common in other buildings where valuables are kept, such as post offices, grand hotels, rare book libraries and certain government ministries.
During its existence, vault technology evolved into an arms race with bank robbers. While crafty burglars kept finding new ways to break into vaults, the manufacturers of them came up with innovative solutions to prevent them from doing so. What would you keep in your vault? | 
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