Investigations carried out by the State Hermitage Laboratory (USSR) established the binding medium of the mural paintings as calcium carbonate and gypsum. The technique is related to the genuine fresco technique with a protective wax coating. The presence of wax preculed the usual consolidation with xylene solutions of pbma-lv (polybutyl methacrylate); a mixture of 3 solvents was used instead. The plaster and paint layer were analysed. The treatment consisted of washing and removal of soluble salts and black mould spots, further consolidation reassembly, and mounting on polyurethane foamed resin. Photographs, references.