Lot 10613 – San Luis Potosi 7c lithographed block of four on Salinas cover

San Luis Potosí 7c dark grey lithographed (consignment #12-1866 sub 15) block of four, a well margined multiple on reverse of cover (opens to display nicely) from Salinas to San Luis Potosí dated September 13, 1866, tied by good strike of the oval « CORREOS / SALINAS DEL P. BLANCO » cancel (Schatzkès #1534). Filing fold affecting the block, fine and very rare. All 7c on cover from any district are scarce let alone in a block of four with this being the largest known used multiple. NF $800 off cover.