Differentiate fixed costs and variable costs. 1  Total cost is the sum of fixed and variable costs.  Variable costs change according to the quantity of a good or service being produced. The amount of materials and labor that is needed for to make a good increases in direct proportion to the number of goods produced.
Xtrata is a top five producer of copper, thermal coal, coking coal, ferrochrome, zinc and nickel and has operations in 19 countries. The company's copper production in 2010 was over 900 thousand metric tons and it has copper facilities located in Australia, Chile, Peru, Argentina, and Canada.
Noble Metals LLC serves many of it s customers in house by sampling and assaying material for gold (Au), silver (Ag), platinum (Pt), palladium (Pd), rhodium (Rh) and iridium (Ir). Noble Metals LLC operates a few smelting furnaces and certain materials are melted off site by other trusted professionals if needed. Nearly all of the actual refining into pure metal is currently done off site. Noble Metals LLC does have the ability to refine material to pure returnable metal by special request.