United Kingdom, The Royal Arms Gold Coin 1 oz 2021, Brilliant Uncirculated. Purity 999.9/1000, Weight 31.10g, Diameter 32.69 mm. Mint: The Royal Mint. The coin features the Royal Arms, a symbol of strength and majesty. The obverse displays the effigy of Her Majesty Queen Elizabeth II, along with the face value of 100 pounds on a guilloche design. The reverse features the current variation of the Royal Arms, with a quartered shield, each representing nations under the United Kingdom. The coin features a radial background, exemplifying the design.