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 is part of a series by the Mint of Poland dedicated to butterflies, and depicts a Parnassius Apollo butterfly.
The Apollo or mountain Apollo (Parnassius apollo), is a butterfly of the family Papilionidae. The species is named in the classical tradition for the Greek god Apollo.
The Mint says about it:
"Another brilliant issue in the captivating Butterflies series of coins bears the title “Apollo” and is dedicated to a beautiful butterfly easily recognised by its lovely coloration, with big black spots on the tops of its wings and red spots on the bottom, and living in the mountainous regions. The creamy-white wings of Apollo are 5-8 cm long with red spots on its fore-wings and back wings. The butterfly uses these spots to deter its predators due to their resemblance to the eyes of an animal. Thanks to the pad printing technique the image on the coin displays the genuine colours of the butterfly. To the right of the image, there is the inscription denoting the Latin name of the insect." | 
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