William IV groat dated 1837.
The groat was reintroduced in 1836 at the instigation of politician, Joseph Hume. It facilitated the payment of exact cab fares and denied cabbies the opportunity of claiming that they had no change for the sixpence tendered in payment. The resulting loss of 'tips' led to them using the derisory name 'joey' (from Joseph Hume) for the coin. The name subsequently transferred to the silver threepence and was in common use until that coin was last struck in the 1940s.