Conservation and restoration of metals

Conservation and restoration of metals is the activity devoted to the protection and preservation of historical (religious, artistic, technical and ethnographic) and archaeological objects made partly or entirely of metal. In it are included all activities aimed at preventing or slowing deterioration of items, as well as improving accessibility and readability of them as objects of cultural heritage. Despite the fact that metals are generally considered as the relatively permanent and stable materials, in contact with the environment they deteriorate gradually, some faster and some much slower. This applies especially to archaeological finds.Sodium thiosulphate 30%Ammonium thiosulphate 15%Potassium sodium tartarate 25%Phosphoric acid 10-20%Trisodium phosphate 15%HCl 5% + ammonium acetate 10%EDTA pH 7Ammonium chloride 10%2 mercaptobenzotiazoleElectrochemical4 methyl imidazoleNaOH/ethylenediaminephosphatingtanninelectrochemicalphosphating Conservation and restoration of metals is the activity devoted to the protection and preservation of historical (religious, artistic, technical and ethnographic) and archaeological objects made partly or entirely of metal. In it are included all activities aimed at preventing or slowing deterioration of items, as well as improving accessibility and readability of them as objects of cultural heritage. Despite the fact that metals are generally considered as the relatively permanent and stable materials, in contact with the environment they deteriorate gradually, some faster and some much slower. This applies especially to archaeological finds. It is very important that a conservator of metals has knowledge of basic metalworking techniques, history of metalwork, history of art, archaeology, corrosion of metals, scientific research methods, theory and ethics of conservation-restoration. An essential cause of deterioration is corrosion of metal objects or object deterioration by interaction with the environment. As the most influential factors of deterioration of historical objects should be pointed out as the relative humidity and air pollution while in archaeological objects a crucial role has composition, depth, humidity and amount of gasses in the soil. In cases of marine or fresh water finds the most important factors of decay are the amount and composition of soluble salts, water depth, amount of dissolved gases, the direction of water currents and the role of both microscopic and macroscopic living organisms.