Machine shop: precision & CNC machining, drilling, boring, cutting, honing, grinding, arc & gas welding, steel fabricating, lathe & mill work Gaseous fuels and additives, Fuel additives, Gaseous fuels, Ferrous alloy, Iron, Lead, Tin, Indium, Palladium, Zinc, Slag or ash, Natural graphite, Steel, Aluminum, Nickel, Bismuth, Antimony, Cadmium