Liberia, 1936, 6¢ on 2¢ Violet, "Via Air Mail" Surcharge. Cockrill third printing (No. 8), slightly tropicalized o.g., fresh with deep color, Very Fine, a beautiful example of this very rare 3¢ Provisional Trial Airmail overprint. Sanabria No. 6. Scott No. C1 var.  Estimate $400 - 600. $0 (Image)