For 2023 the Royal Mint released a very Limited Issue Britannia £25 Twenty Five Pound Platinum Proof Coin struck in solid fine 999.5 Platinum weighing one-quarter of an ounce of fine pure Platinum.
The reverse designed by Jonathan Olliffe features Britannia driving a sea chariot pulled by horses as aquatic and serpent-inspired creatures with traditional equine figures while the obverse features the First Portrait of His Majesty King Charles III by Martin Jennings.
These legal tender coins have been struck to proof quality using specially prepared dies and highly polished blanks.