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).
This coin is part of the "Czech Lion" series of gold and silver coins, minted since 2017 with a new design every year. The weight of this silver coin by the Czech Mint is one troy ounce. It is a reverse proof - mirror designs on frosted surfaces - and differs from the regular bullion silver ounce. The regular silver ounce has a design which matches that of the small gold pieces, while the reverse proof silver has the design of the higher denominations.
The Mint says about it:
The author of the original 2019 composition was medal maker Jaroslav Bejvl, who left us forever at the age of 75, so he did not manage to finish his masterpiece; Asamat Baltaev completed this masterpiece. The reverse side of the coin is dominated by a non-traditionally realistic two-tailed lion which guards the St Wenceslas crown, along with a flaming eagle on the shield. | 
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