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 internationally popular one ounce of silver format (abbreviated as 1 oz Ag, where "Ag" comes from the Latin word for silver, Argentum). 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.
This coin commemorates the 60th Anniversary of the coronation of Queen Elizabeth II, who is not only the Queen of the United Kingdom but also the Queen of New Zealand.
NZ Post (the issuer of the coin) says about it:
The design of the coin features the six main portraits of the Queen that have appeared on New Zealand legal tender coins. The frosted finish and three-dimensional relief applied to the portraits provide a striking contrast to the polished background. The first five portraits are beautifully engraved on the reverse side of the coin, while the obverse side of the coin features the Queen's portrait that appears on New Zealand coins today - designed by Ian Rank-Broadley.
The coin design shows how the Queen has changed through the years - from a youthful Queen in Mary Gillick's 1953 design to an experienced monarch in Ian Rank-Broadley's 1999 design. | 
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