Production of the first coins featuring King Charles III for circulation has started at the Royal Mint, beginning the transition from Queen Elizabeth II to her son’s portrait on the nation’s coinage.The new coins will be going into circulation by December, meaning many will see them in their pockets over the festive period.In memory of the late Queen, the Royal Mint is also producing 9.6 million memorial 50 pences in tribute to her 70-year reign.The reverse side of the King's coin features the Royal Arms and emblems of the four nations.