COLOMBIA, 1921, "30c" on 50c Pale Green, Air Post Surcharge (Colomphil 12; Scott C22b).
With sheet margin at left, tied by violet "Sociedad Colombo Alemana de Transportes Aereos" three-line cancel of Bogota and used with National 3c (faulty) on cover front only to Barranquilla, front with few file folds, one affecting National stamp, 30c with light toned spots, still of Fine appearance, this is the unique
example on cover front with no complete covers recorded, only a small handful of used singles are believed to exist, similar to Colomphil No. 13 but differentiated from No. 13 having more of a "skeleton" outline of the surcharge likely caused by different inks used, listed but unpriced in Scott
Image Magnifier / Download
Power Search for Comparables