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, bullion 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 - typically, one ounce of silver (abbreviated as 1 oz Ag, where "Ag" comes from the Latin word for silver, Argentum). Many of these feature various animals.
This coin is part of a series by the Mint of Poland dedicated to butterflies, and depicts a Maculinea Arion butterfly.
The Mint says about it:
"The Mint of Poland is proud to present a new series of collector coins, theButterflies. The collection features the most beautiful and unique butterflies of Europe and world. The coins in the series have a limited mintage, up to 8,000 pieces, an original design and an interesting theme. Thanks to the pad printing technique the images reflect the genuine butterfly colours.
The Large Blue (Maculinea arion) is a diurnal butterfly of the Lycaenidae family. It has very characteristic, beautiful blue wings, speckled with black dots. The wingspan reaches 4 cm. Sexual dimorphism is only minimal, with the female being better identifiable by its more intensive wing drawings. The large blue butterfly is commonly spotted between the latter half of June and early August. Isolated individuals live as short as a few days, sometimes up to two weeks or so. They usually feed off thyme flowers, but are also found feeding off vicia. They like to spend the nights and the hottest times of day among juniper bushes. Females lay the eggs in the flowers of burnet. When the larvae are big enough they fall down onto the earth. Secreting honeydew they attract the red ants, which take them to their nests. The large blue caterpillars spend there up to 10 months feeding off ant larvae and eggs." | 
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