The Tuvaluan Dollar is the currency of Tuvalu - a small nation in the Pacific Ocean. Tuvalu has never had banknotes of its own, and has been issuing coins since 1976; these circulate together with coins of the Australian Dollar, which is also legal tender in the country, and to which the Tuvaluan Dollar is pegged.
The Australian Perth Mint issues a large variety of non-circulating legal tender (NCLT) coins under the authority of Tuvalu. Some of these are in the one dollar denomination, and have the same specifications that the mint uses for its large non-circulating Australian dollar range; these are larger than the normal circulating dollar coins.
This coin was issued in celebration of the Chinese New Year 2018 (16 February 2018).
The Mint says about it:
The Perth Mint and Australia Post are pleased to celebrate Chinese New Year with a stunning Postal Numismatic Cover. Resplendent in ancient Chinese symbols of good fortune, this coin features a dragon in the shape of a Chinese knot. The dragon represents wealth and power, while Chinese knots have been used for centuries as good luck charms. In the background is a traditional temple, Chinese lanterns and the Chinese characters for "Happy New Year".
This uncirculated aluminium bronze coin is issued as legal tender under the authority of the Government of Tuvalu and features the Ian Rank-Broadley effigy of Her Majesty Queen Elizabeth II, the monetary denomination, and the 2018 year-date on the coin’s obverse. | 
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