GRIQUALAND 1878 SG15a Mint ½d grey-black type 16 overprint inverted

1878 (June) ¬Ωd grey-black, type 16 opt (inverted), block of 32 (4x8) with wing margin at right, o.g. (many unmounted). Being inverted, the overprint is that intended for right panes, when upright, with a combination of types 15 and 16 (type 15 at R1/6, 4/5 and 6-10/6 only), whereas the other pane shows type 15 throughout. Odd minor tones and gum wrinkles, but exceptionally fresh, and overall in a remarkable state of preservation for such a multiple. Very scarce. [N.B. The complete two-pane setting of 120 was usually applied upright to the upper panes, but INVERTED to the lower panes, on a "print and turn" basis.] - P223011009