Although iron in minute amounts is necessary for the metabolism of most cells, it produces damage if present in excess. Clinical tools for the evaluation of iron stores include serum iron concentration, transferrin saturation, deferoxamine test, Prussian blue stains of liver and marrow, and serum ferritin concentration. Serum ferritin concentration is an excellent screening test for iron deficiency or excessive iron stores. If excessive iron stores is diagnosed, the iron should be removed with phlebotomies or chelation therapy.