Niue, a sovereign state in free association with New Zealand, uses two official legal tender currencies. The New Zealand Dollar is the circulation currency for daily transactions, while the government also authorises legal tender coins in the Niue Dollar currency for collector's purposes.
A number of mints issue a large variety of commemorative and collector coins under the authority of Niue. These coins are dedicated to historical or general popular culture themes not related to Niue itself. Many of them are in standard bullion sizes - such as a half ounce of gold (abbreviated as 1/2 oz Au, where "Au" comes from the Latin word for gold, Aurum).
This coin commemorates the Centenary (100th anniversary) of the Royal Air Force (RAF), which was founded in 1918, and was issued in a two-coin set together with a British coin marking the occasion.
The Czech Mint says about it:
The Royal Air Force of the United Kingdom is the oldest independent air force in the world. It was formed at the end of the First World War in 1918 and was renowned during the Second World War, when it fought its most famous campaign, the Battle of Britain. At that time the island kingdom desperately needed help, and so dozens of Czechoslovak airmen, who had lost their homes because of Nazi occupation, were also involved in the fight.
"Never was so much owed by so many to so few", Winston Churchill told his faithful pilots. "If the Czechs and the Poles did not help the Royal Air Force, we would not have won the battle for Britain", added Squadron Leader George Blackwood, saying that in the event of a loss in the air, nothing would prevent the amphibious German invasion. By the end of the war, the number of Czechoslovaks serving in the RAF had grown to two thousand and at home and abroad they are still remembered as heroes.
The coin of the Czech Mint was made by the academic sculptor Zbyněk Fojtů, who has rich experience in RAF themes. The obverse designer is Ladislav Vraný. | 
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