1966 British penny mule with Jersey obverse
In the 1960s the Royal Mint was striking coins for many overseas countries; not just Great Britain and its Crown Dependencies. In 1966 many British pennies were struck in the lead-up to decimalisation, and a comparatively small number of Jersey 1/12th of a shilling were also struck. There was apparently a mix-up during production of the coins as a small number of 1966 British pennies were struck with the obverse for a Jersey 1/12th of a shilling.
Just two examples of mule are known, though it is not known whether they were found in Great Britain or Jersey. One example was sold as lot 124 in the Colin Cooke auction of The James Workman Superior Collection of Pennies Part 2 in November 2010 but no provenance was given. The other example has not been sighted in a sale in recent times.