The process of locating,mining and extracting metal is incredibly resource intensive, even for native metals. For example, miners must process roughly 33 tons (nearly 30,000 kilograms) of rock and earth to produce a single ounce (28 grams) of gold .When it comes to non-native metals like aluminum or lead, the process can be even more complex and time consuming.
Once metal ore has been extracted from the earth, it's crushed by rock cruhser and grounded in mill to separate the rock from the metal. Mining companies then use one of three processes to transform this raw metal into a final product. The oldest and most economical option involves heating the metal in a furnace to produce a carbon-reduction process. Other metals require the use of electrolysis to separate impurities and any remaining rock from the metal ore. Finally, these companies may use chemicals to purify and decontaminate the metals. For example, sulfuric acid can be used to process copper ore, and sodium-based chemicals aid in the separation of aluminum oxides.