This Spanish commemorative stamp was issued in 1968 to celebrate Día Mundial del Sello (World Stamp Day). The design reproduces the classic 1850 6 Reales blue stamp featuring Queen Isabella II, one of Spain’s earliest postage issues. The modern stamp bears a denomination of 3.50 pesetas and was printed by F.N.M.T. (Fábrica Nacional de Moneda y Timbre).

The black rectangular “SERRANA” cancellation adds a vintage charm, enhancing its appeal for philatelists interested in postal markings. This issue beautifully bridges early philatelic history with mid-20th-century commemorations, symbolizing Spain’s long postal tradition.