Ключевые слова: aluminum, antimony, bismuth, cadmium, chrome, cobalt, copper, gallium, graphite, grey, illustration, indium, iron, lead, lic, mercury, metal, molybdenum, nickel, osmium, palladium, pewter, platinum, rhodium, ruthenium, silver, steel, tantalum, titanium, tungsten, vanadium, zinc, zirconium,