Gracie, what are you saying the stamp design is measuring, both top to bottom and side to side--design only, not perf to perf.? For it to be #594, it needs to be 19¾ x 22¼. For it to be #596, 19¼ x 22½. Both these stamps perf. 11x11, both are Green. The color on your scan looks right the cancel is good--although almost all #596s are precancelled from Kansas City Mo., some do have the cancel yours has. If it meets these criteria, get it certified.
