Issued in 1968, this striking 6 Francs Europa stamp from Luxembourg features the iconic CEPT “key” design symbolizing cooperation and unity among European postal administrations. Designed by H. Schwarzenbach and printed by Courvoisier S.A., it showcases a stylized golden key with the letters C-E-P-T (Conference of European Postal and Telecommunications Administrations) on a deep orange background. This issue forms part of the common Europa design series adopted by multiple countries that year, reflecting the spirit of European integration and communication. A must-have for Europa-themed and Luxembourg collectors alike.