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.
One of the formats used is the half gram of gold (0.5 g) mini-coin, in which this coin is made.
The mint says about this coin:
"The Noble coins have been issued by Isle of Man since the early 1980’s. They are not minted every year, but have an erratic schedule. Nobles are legal tender but they do not have a fixed face value; instead, like the Krugerrand or Mexico’s Libertad, they are legal tender to the value of their precious metal content. This .9999 gold proof edition with a size of 11 mm and a weight of 0.5 g will surely be a significant item in any collection. It is meant as a perfect complement to the silver piedfort coin."
It is usually said that 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, under section 6 of the Currency Act 1992, the "Noble" denomination is 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 half gram is 5/64 of a pound, or 0.078125 p (rounded up to eight pence). | 
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