New Zealand uses the New Zealand Dollar as its circulation currency for daily transactions. The country also issues a number of commemorative and collector coins, including in the very large five ounces of gold format (abbreviated as 5 oz Au, where "Au" comes from the Latin word for gold, Aurum). Authorised by the Reserve Bank of New Zealand, the official issuer of these coins is NZ Post - which also issues the country's postal stamps. Manufacturing of the coins is commissioned to various foreign mints.
The coins are "Non-Circulating Legal Tender" (NCLT) and not bullion because they are issued at prices much higher than their intrinsic value and are targeted at collectors who appreciate them for their artistic or sentimental value, and not at bullion investors.
NZ Post (the issuer of the coin) says about it:
This 5oz gold proof coin captures all the intricate details of the taniwha. Each scale and facial feature can clearly be seen in this detailed portrayal. Other cultures have dragons, serpents or other mythical beasts at the heart of their myths and legends, New Zealand has the taniwha.
The taniwha was a dominant creature in Māori legends, portrayed as a terrifying beast or a protector of tribes. The exact characteristics of the taniwha often changed, sometimes it was portrayed with wings, other times it was a serpent or a terrifying sea monster.