Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. Most of these by tradition are measured in troy ounces of fractions thereof, but the mint also introduced metric coins measuring one kilogram of pure metal (they are actually fractionally heavier as a whole, to account for the small amount of other metal in the alloy).
The 1 kg gold coins are denominated as One Thousand Pounds (£1,000), although their intrinsic (bullion) value is much higher than their face value. The coins vary in design depending on the occasion (they are "one-year" types usually issued in parallel with smaller denominations with the same reverse designs).
The coins are legal tender but are not intended for circulation. They are targeted at bullion investors or collectors who appreciate the special editions as pieces of art.
This one kilogram gold coin was issued by the Royal Mint as part of an extensive coin series dedicated to the upcoming XXX Olympiad, also known as the 2012 Olympic Games in London. It is also the first gold coin of this size issued by the mint.
Issuing this new size required a new act of Parliament and legislation in order to authorise its production. The amendment in the legislation removed the upper limit of weight of a UK coin. It was also the first coin to have a face value of £1000.
The reverse was designed by Sir Anthony Alfred Caro OM CBE (1924 - 2013), an English abstract sculptor lauded as the greatest British sculptor of his generation, whose work is characterised by assemblages of metal using "found" industrial objects. His style is of the modernist school. | 
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