... Originally intended for use in transport, as bus fare for example
... a reverse design modified by Percy Metcalfe after sketches originally submitted in June 1936 by Miss Frances Madge Kitchener,
niece of military hero Lord Kitchener.
Miss Kitchener's conception for the coin, introduced as a type in this pattern, was for a sideways-appearing trio of thrift, or thistle plant,
flowers atop curling tendrils.
The idea for the reverse motif surely had been borrowed from the 1928 Irish Free State coinages which introduced the use of 'native flora and fauna' for reverse designs in place of the traditional royal insignia,
and in subsequent commercial versions the coin proved popular, useful and durable.
Two models of this were prepared in 1936 but abandoned as overly ornate, in favor of a less realistic or more deco-styled image of the plant,
but showing fuller flowers, which was finally adopted for the brass coinage of George VI later in 1937.
Source: Heritage to Offer Rare British Threepence Piece!