Rheinish reliquary shrines, of which the best known is the Shrine of the Three Kings in Cologne. The Shrine of Marsus was made of gold and decorated with numerous gilt enamel plaques and gems. The largest of these was an image of Emperor Otto II on the backside of the shrine, which based on a depiction of the shrine in an altarpiece depicted Otto in worship and also acted as a memorial. This first large chasse was destroyed as a result of the stupidity of the Abbey servants responsible for evacuation in 1794, when it was taken to be safe from French plunder. The remains were melted down, and a masterpiece of Ottonian art was irreparably lost. Mathilde is probably also the donor of the more than life size Triumphal cross in the Aschaffenburg Abbey church of St Peter and Alexander, whose paintwork corresponds to the edging decoration of the Cross of Otto and Mathilde. Since Mathilde's brother Otto was buried in this church, this cross was probably part of his memorial. Mathilde's building programme Georg Humann, the first art historian who concerned himself with the buildings and artefacts of Essen Abbey had ascribed the westwerk of Essen Minster to Mathilde by means of stylistic comparisons. Subsequent research has affirmed this understanding; Mathilde is seen as the initiator of the westwerk, which since the excavation of a predecessor building in 1955 by Zimmerman had been considered mostly the work of Abbess Theophanu who reigned 1039-1058. Mathilde is therefore also responsible for the earliest plumbing yet found at Essen, a lead pipe which ran transversely under the Weswerk and throughout the Abbey buildings. Such water pipes were uncommon in the Early Middle Ages and only found in opulent buildings; they therefore indicate the prestige of the builder. The question of whether this was Mathilde or Theophanu was uncontentious, but a change in building style did occur in this time. Had the Essen westwork—a masterpiece of Ottonian construction—first been built under Theophanu, it would have been built later than one of the masterpieces of the succeeding Romanesque style, St Maria im Kapitol in Cologne (which was built by Theophanu's sister Ida). On the other hand, Theophanu is praised for rebuilding the Essen cloister in the Brauweiler family chronicle of the Ezzonid family (of which Theophanu was a member). The work carried out by Zimmerman supported the latter position, which also held that