Elizabeth II, 10 Pence, 1968 UNC
In fact the Royal Mint issued a set of coins for the new Decimalisation which contained three coins dated 1971 and two dated 1968. The 10 Pence and the 5 Pence were dated 1968 as they had an exact decimal equivalent.
This older large sized 10 Pence was dated and issued in1968, three years before the coins were going to be issued. The set was to train people in the new decimal coinage. This 10 Pence is in Brilliant Uncirculated condition and a lot of collectors are missing it from their collections.