DERBYS/BUTTERLEY UDC. 1851 entire from "Butterley Iron Works" to Bradford, Yorks with fine four margined 1d imperf (SG8) lettered JA tied "6" barred numeral of Alfreton and on reverse very fine strike BUTTERLEY udc in blue (DY66) and ALFRETON date stamp also in blue AP 7 1851. This strike of the udc is the one listed in the County Catalogue. (Ref 99277).