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 and collector coins under the authority of Niue. One of them is the Czech Mint, which uses not only standard bullion sizes but also some formats based on the Czech Gold Ducat, including 40 Ducats weighing a massive 139.5 grams.
The coins are "Non-Circulating Legal Tender" (NCLT) and not bullion because they are issued at prices much higher than their bullion value and are targeted at collectors who appreciate them for their artistic or sentimental value, and not at bullion investors.
The Mint says about this coin:
This coin commemorates the beginnings of the Přemyslid dynasty. Bořivoj I was the first Czech duke and Christian ruler - and member of the Přemyslid dynasty - who largely contributed to the spread of Christianity in the Czech lands in the 9th century. He and his wife Ludmila were baptised by archbishop Methodius and built the first churches on the territory of central Bohemia. | 
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