1880 (Jun 23) 10c original plate proof sheet of 10 (5x2) in black on thin card, with red hand stamped date at upper right, Insignificant purple marks at lower right, a unique and important showpiece with impressive provenance,ex Walter Bickly, Cassels (Spink 11/2006, lot 1672) , Lahner (Spink 12/3/97, lot 314), Burnett (CRL 10/84, lot 487) and Danson. (Image)