Tulane University defines an ore as a body of material from which one or more valuable substances can be extracted. For example, bauxite ore is mined and refined to extract aluminum.
Most materials are not mined from the ground in their finished state. They are usually part of ores that are mined and then refined to extract the wanted materials. Tulane University emphasizes that the concentration of the desired material in the ore compared to the cost of mining and extracting the wanted material helps determine the economic feasibility of a given mine. Minerals in an ore deposit that do not contain the desired material are referred to as gangue.