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 coins under the authority of Niue. Most of these are commemorative and collector issues dedicated to historical or general popular culture themes not related to Niue itself. Many of them are in standard bullion sizes, including one ounce of gold (abbreviated as 1 oz Au, where "Au" comes from the Latin word for gold, Aurum). Those issued at prices much higher than their bullion value are separately listed in the Non-Circulating Legal Tender (NCLT) gold ounce section of the site.
Unlike them, this coin is targeted at bullion investors and was initially released at a price close to the value of its precious metal content.
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 gold 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 gold ounce. The regular gold ounce has a design which matches that of the small gold pieces, while the reverse proof 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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