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.
The 2024 Year of the Dragon coins are part of the Royal Mint's Shēngxiào Collection - a coin series dedicated to the Chinese Lunar calendar.
The mint says:
"The Lunar Collection continues with a coin celebrating the Year of the Dragon. Those born under this sign are said to share many of the dragon’s desirable characteristics such as confidence, courage and adventurousness."
The range was released on 4 September 2023, in advance of the Chinese Lunar Year of the Dragon (10 February 2024 - 28 January 2025). | 
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