Banco Central de Venezuela, 1950-56 issue, 10, 10, 10, 10 Bolivares, all face essay mock ups, some elements engraved, others hand drawn, all unadopted designs unlike anything actually circulated, first without portrait which would be at center, others with design elements complete, also a matted photograph of one of these designs, together with 10, 10, 20, 20-Bolivares, all back essay mock ups, one with denominations missing at corners, all rare and unusual, crisp uncirculated, illustrated (9) (lot)