CSA 7-R, 5¢ blue vertical pair used privately over CSA Nitre and Mining Bureau imprinted envelope (UNLISTED TYPE) tied RICHMOND Va. CDS, addressed to Prof. Wm Caruthers, Hampden Sidney P.O. Prince Edward Co. Va. docketing “Ans. April 26th 1863,” top back flap missing and slightly reduced at top, stamp moved aside to display imprint. Ex David Burton. $550.