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 silver coins are denominated as Five Hundred Pounds (£500), 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 commemorative coin celebrates 200 years since the birth of Queen Victoria and Prince Albert.
The Royal Mint says:
"There is no better canvas for numismatic art than the kilo coin, offering the viewer an opportunity to view the precision and craftsmanship of The Royal Mint in detail.
Here, a classic portrait of Queen Victoria and Prince Albert is revived in honour of the 200th anniversary of their births, both having been born in 1819. Originally issued as a medal for the Great Exhibition of 1851, the coin's design was created by former Royal Mint Chief Engraver William Wyon. It captures the progressive couple in the peak of health and ambition, embodying the spirit of their age." | 
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