1915, Mafia Island, 1 A carmine I.E.F. stamp with additional overprint 'G.R / POST/ MAFIA' in blue, single franking on cover to Zanzibar, arrival mark of British Post Office Zanzibar, MR 28 16, on reverse. Envelope slightly shortened at right and negligible creases not affecting stamp, else fine condition. VERY RARE commercial mail from the British Occupation of Mafia Island! (Image)