Ключевые слова: aluminum, antimony, beryllium, bismuth, chromium, cobalt, gallium, gray, hafnium, illustration, indium, iridium, iron, lead, magnesium, metal, molybdenum, nickel, niobium, osmium, palladium, pewter, platinum, rhodium, stainless, steel, tantalum, thallium, titanium, tungsten, vanadium, zinc, zirconium,