Auction 333-341 Nigeria, Cameroon, Sudan & Worldwide Postal History - Day 4

Niger Coast Protectorate 1897: Registration Envelope, 2 d. ultramarine, size K, franked with horizontal pair 1894 2½ d. pale-blue, sent from Old Calabar to Borna, Germany, dated 3 January 1899, cancelled by "OLD CALABAR RIVER" cds, a "REGISTERED OLD CALABAR" oval alongside, also a "REGISTERED LIVERPOOL" dated 2 February 1898 and a red "REGISTERED LONDON" oval dated 3 February 1899. To the reverse an arrival "BORNA / LEIPZIG" 4 February 1899. In remarkable condition, just minor imperfections to edges, very rare; one of two non CTO used examples.
Reference: The Postal Stationery of Nigeria, by Peter Hørlyck, pg. 54 & 421.