smelting or refining
(2) the term “smelting or refining” embraces only pyrometallurgical, hydrometallurgical, electrometallurgical, chemical, or other processes— (A) for the treatment of metal-bearing materials to reduce the metal content thereof to a metallic state in the course of recovering it in forms which if imported would be classifiable in chapters 71 through 83 of the Harmonized Tariff Schedule of the United States as unwrought metal, or in the form of oxides or other compounds which are obtained directly from the treatment of materials provided for in chapter 26 of the Harmonized Tariff Schedule of the United States, and (B) for the treatment of unwrought metal or metal waste and scrap to remove impurities or undesired components; and