<P> Work on the new mint began in August 1967 with the construction of a blank treatment plant and plant for striking . This first phase of the mint was officially opened on 17 December 1968 by the royal attendance of Queen Elizabeth II , Prince Philip and their son Prince Charles . Originally there were fears that the Royal family would face protests because of the Investiture of Prince Charles as the Prince of Wales ; however , such protests failed to materialise . The second phase of construction began in 1973 and included the addition of a means to mint coins from virgin metals completing the full minting process . Upon completion the final cost for the land , buildings and plant came to £ 8 million . Coin minting and production gradually shifted to the new site over the next seven years until the last coin , a gold sovereign , was struck in London in November 1975 . In an attempt to consolidate all previous coin - related acts , the Coinage Act of 1971 was passed , which among other things effectively abolished the individual role of Master of the Mint . Under this act , the Chancellor of the Exchequer took over the role , with a Deputy Master being appointed by the Treasury to exercise all the powers and duties of the Master within the mint . </P>
when did the royal mint move to wales
1968