Watch List notes:

The Milton Collection, British West Africa, George VI, shilling, 1952, trial striking in chromed-steel, crowned bust left, by Percy Metcalfe, legend without IND IMP, "TRIAL" in small raised capital letters before face, rev. palm dividing date, value below, "TRIAL" in small raised capital letters above 52 of date (FT 326; KM TS3), a choice example, certified and graded by NGC as Mint State 67
Ex Carl F. Chirico Jr. Collection of World Pattern Coins, Bowers and Merena Auction (7 March 2008)
A number of these trial shillings were minted in the 1950s with which to test vending machines.
(300-350 GBP)