handstamped in dull violet on 2a. vermilion, initialled "A.D" (Andrew Dick, the Chief Accountant); one short perf at top otherwise fresh and fine unused with part original gum. Rare. B.P.A. Certificate (1986). S.G. 20, £3750. Photo" /> unused 1891 Mombasa Provisional,<I> "½ Anna"</I> handstamped in dull violet on 2a. vermilion, initialled<I> "A.D"</I> (Andrew Dick, the Chief Accountant); one short perf at top otherwise fresh and fine unused with part original gum. Rare. B.P.A. Certificate (1986). S.G. 20, £3750. Photo | Christie's