Conservative Characteristics of the plaster coating the Red Sacellum of Monte d'Accoddi (Sardinia)

The results of characterizing the pigmented plaster partially coating a "sacellum" housed in a prehistoric megalithic monument situated in north Sardinia are presented here. In terms of construction materials, the plaster is by far the most interesting. Its micro-structural features share nothing in common with historic mortars, the constituents being extremely fine and traditional binders absent. Because of its intrinsic weakness, exacerbated by temperature and humidity variations in the "sacellum", the plaster has been reduced to an extremely precarious state. Tests on specimens, prepared in the laboratory using raw mixes similar to the original plaster constituents, confirmed this trend.