Canada 711a1978 Ten cent Lady's Slipper, CBN printing; Plate 2, perf 13x13. 3, right margin mint block of fifteen, the centre strip of three with a dramatic Repellex colour error, almost completely missing colour on the top and lower stamps of the strip (tagging as well), centre stamp with tan background and green colours missing. Only three such multiples are reported; one of which was split up. A striking and very rare block, Very Fine, Never Hinged(Unitrade