The portable altar of Stavelot is an unquestionable masterpiece of medieval enamelwork. The execution of its sumptuous champlevé decoration required as many successive firings as there are colours, as each of the metal pigments mixed with powdered glass reaches its melting point at a different temperature. It is the result of true technical prowess. The iconographic programme, combining narration and symbolism, is on a par with the quality of execution; on the top, the story of Christ's Passion is depicted alongside Old Testament episodes prefiguring the main episodes of the Passion cycle. The sides recount the martyrdom and death of the Twelve Apostles. The whole is completed by figures of the Evangelists, a direct reference to the message of salvation represented on the top and conveyed in the Holy Scriptures.