Obverse: CONSTANTINVS IVN N C Reverse: BEATA TRANQVILLITAS BM 1975, 1008.4 RIC VII London -- . Photo courtesy of the British Museum and reproduced here in accordance with their conditions of use.
A coin in the British Museum collection and as far as I am aware, the only known example of this obverse type attributable to the London mint. Unrecorded in RIC for London, there are examples known from Trier but these are still very rare. The obverse bust type shows Constantine II with a decorated shield and cuirass holding a horse by the bridle with his right hand.
This and many other types unrecorded in RIC will appear in my next article - The London Mint AD 319 to AD 325 - due to be published in Spink's Numismatic Circular later this year. Over forty new types will be added to the 147 types originally recorded in RIC VII.