Dominica SG133/a 1.20 R8/4 with C of CA in watermark omitted RARE Cat 1380 pound

Dominica SG133/a 1951 1.20 block of twenty the bottom four rows of the sheet with Plate 1-1 and BW imprint unmounted R8/4 with C of CA in watermark omitted this stamp with a very small natural inclusion. Stamp R9/1 shows part of the C in watermark omitted. A Rare piece