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 90th Birthday of Queen Elizabeth II on 21 April 2016.
NZ Post (the issuer of the coin) says about it:
This beautiful 1oz silver proof coin features the Duke and Duchess of York (later King George VI and Queen Elizabeth, the Queen Mother) pictured holding their daughter, Princess Elizabeth (later Queen Elizabeth II) as she sleeps in a precious christening gown. The christening gown has been used by the royal family for generations, with a faithful replica used today for the newest additions to the royal family. The photo has been printed using a minted photo image technique, replicating the photographic look from days gone by. The photograph is framed by beautiful, high relief gold plating featuring New Zealand’s pōhutukawa flowers. | 
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