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

Biafra 1969: Air letter form franked with 1968 1st Independence Anniversary 2 s. 6 d. postage, used from Owerri to Illinois, USA, dated 5 December 1969, cancelled by "OWERRI" datestamp in black. Some wrinkles as is expected and a vertical fold well clear of adhesive. A rare commercial use.
Note: The sale and use of the unstamped aerogrammes apparently caused confusion, so later the aerogrammes were sold pre-stamped with a 2 s. 6 d. postage stamp.
Reference: The Postal Stationery of Nigeria, by Peter Hørlyck, illustrated pg. 300.