Lot 42121 – 1914-26 Waterlow Seahorse 12p on 10s indigo-blue with « SPECIMEN » ovpt (type GB23) in mint n.h. lower marginal block of 8

1914-26 Waterlow Seahorse 12p on 10s indigo-blue with « SPECIMEN » ovpt (type GB23) in mint n.h. lower marginal block of 8, from plate HV4 with proving centre-guide, with pencil « AM » initials in lower left corner and « L » at lower right, slight gum disturbance in lower margin and a little perf. separation in right corner, an important and spectacular positional multiple, unique in private hands (from the one sheet of 40 released); ex BPMA archives.

Note: The usual 10s UPU « SPECIMEN » ovpt is a different type (GB26).