It's unclear exactly what date the first Northern Nigeria stamps were issued, shipping arrival times from London suggest late March, or more likely early April 1900. Stamp collectors recognise 5 different sets issued between 1900 and 1912 plus a £25 stamp inscribed “Postage & Revenue”. Northern Nigeria’s rarest stamp is the 1904 £25 green & carmine which at the time of writing is catalogued £60,000 in mint condition and is not known used with a postmark, however fiscally used examples do exist. For budgetary reasons Northern Nigeria utilised the De La Rue Universal Key Plates for her stamps and these beautiful issues are highly collectible. Like the rest of the Nigerias the postmarks are of interest, the Lokoja cancellations applied to British stamps prior to the arrival of the first set being of particular interest.