South Africa SGO4w 6d Official Pretoria Printing Wmk INVERTED BLOCK of FOUR

Official. 1926 (1 Dec) Set 2 (= 1927 issue) 6d green and orange SG type O1 opt on Pretoria ptg variety INVERTED WMK in a block of four used with characteristic ROSEB(ANK CAPE) cds. Minor marks on reverse and lower pair with a couple of shortish perfs. Still a fine and very scarce block. Possibly only one sheet existed although a single pair is known used at Pretoria. Ex Matheson (Union Handbook O9) (Cat 950++)