What is involved in processing a mineral resource?
Except for certain nonmetallic minerals, mineral resources usually must be separated from the other materials with which they occur. The separation of minerals such as diamond, mica, and rutile is relatively simple, usually involving only simple hand or mechanical processes. The processing of metallic ores is closely related to the complexity of the ore itself and to the needed purity of the desired end product. Certain elements are deleterious to the refining process, and attempts to eliminate them early in the processing stream ensue. For example, sulfur is a poison in the processing of iron ore; some ores must be roasted to drive off the sulfur as sulfur dioxide gas; manganese is added later in the process to get rid of the small quantity remaining.
