unmounted mint Block Larger Than four Spain, Pan-American Postal Union Congress, 1931, selection of mint blocks of twenty-five comprising nos. 491-492, 494, 496-498, 500, C62-C65 (2 of each denomination), C66-C67, CO1-CO6, O20-O24, O26-O28, full o.g., never hinged, one sheet of C65 has small h.s. applied on the reverse of each stamp, few perf. separations or light bends, one 5c (no. 491) torn, vast majority fine-very fine, Scott retail $856.25