The Double Florin (4/-) was one of the shortest-lived British coin denominations ever, only being produced between 1887 and 1890. The silver coin weighed 22.6 grams and was 36 millimetres in diameter.
The obverse side of the coin shows a portrait of Queen Victoria wearing a veil, with the inscription VICTORIA DEI GRATIA, while the reverse shows four cruciform crowned shields bearing the emblems of England (x2), Scotland, and Ireland, with sceptres between the shields, in the style of Charles II's gold coins designed by John Roettier; the inscription on the reverse says FID DEF BRITT REG date.
The Florin or Double Leopard was an attempt by English king Edward III to produce a gold coinage suitable for use in Europe as well as in England (see also Half Florin or Leopard and Quarter Florin or Helm).
The florin, based on a French coin and ultimately on coins issued in Florence, Italy, in 1252, was a standard coin widely used internationally, with a value of six shillings.
Unfortunately the gold used to strike the coins was overvalued, resulting in the coins being unacceptable to merchants, and the coins were withdrawn after only a few months in circulation, in August 1344, to be melted down to produce the more popular gold Noble.
Note that all Maundy coins (which originate in the pre-decimalisation era and have a different design from 'standard issue' coins) are legal tender in the UK, and so while the standard one and two penny coins originate in 1971, the oldest legal tender one and two penny coins date from 1822.
In 1920, the silver content of all Britishcoins was reduced from 92.5% to 50%, with a portion of the remainder consisting of manganese, which caused the coins to tarnish to a very dark color after they had been in circulation for a significant period.
The weight of this coin was instituted by Charlemagne, and the purity of 92.5% silver (sterling silver) was instituted by Henry II in 1158 with the "Tealby Penny" – a hammered coin.