The Isle of Man has its own circulating coinage, which is used in parallel with the British Pound Sterling; it also issues an extensive range of commemorative coins for collectors, as well as bullion coins in a variety of formats and designs for investors in precious metals.
These coins are usually in internationally popular standard formats, but some (such as this coin) are in non-standard sizes. They are considered Non-Circulating Legal Tender (NCLT) because they are "premium" editions released at prices much higher than their bullion value.
This coin is part of the extensive Noble series, depicting a Viking ship. The original Noble denomination was a coin introduced by King Edward III in 1344, which was one of the first widely-used gold coins struck in England. It was believed at the time that the coin was a lucky charm as a protection against thieves. It was discontinued after the reign of King Edward IV, until the Isle of Man revived the denomination in 1983. The strong Viking theme of its design relates to the history of the island, having once been the Kingdom of Man and conquered by Norse leaders, with the King of Dublin and the Earls of Orkney ruling the isle.
This edition celebrates the Diamond Jubilee of Queen Elizabeth II (60 years on the throne).
It is usually said that modern Nobles are legal tender but without a fixed face value, like the Krugerrand or Mexico’s Libertad which are legal tender to the value of their precious metal content. However, according to the various Currency Determinations by The Treasury of the Isle of Man authorising each issue, the "Noble" denomination has a fixed value - for example, the 2010 Determination sets it as £10, while the 2017 and later acts make it equal to 5 pounds in face value, with fractions or multiples divided or multiplied as required by the fraction or multiplier shown on the reverse of the coin. Hence, the one ounce has a nominal face value of £5 (five pounds). | 
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