This one troy ounce coin was first issued in 1987, and the Britannia is Britain’s Royal Mint’s version of the bullion coins like Krugerrands or American Gold Eagles. As with those other coins, the intention is to give the public and individual investors a convenient way to own gold bullion at a low premium over the spot price of gold. Like the other coins, there are once ounce, half ounce, quarter ounce and one tenth of an ounce weights. The fractional sizes attract more of a premium, and are much harder to find.
Both sides of the Gold Britannia, 1oz version
One side of the coin features the monarch, and the other side has Britannia herself, the personification of the country first used on Roman coins of the emperor Hadrian. Even the modern design of standing Britannia features her wearing a Roman style helmet and holding a trident.
The one ounce Britannia has a face value of £100, has a diameter of 32.69mm, weighs 34.0 grams, and has 31.104 or exactly one troy ounce of gold. The alloy used to harden the coin was copper until 1990, then silver was used instead. Proof versions of the coin are also available, at a premium.
More gold Britannia sources
Coin Dealers in the British Isles – http://www.numis.co.uk/