Technical Abstract: Good mineral nutrition is, in part, a geologic issue. Sixteen mineral elements are known to be essential for good health. These, collectively, have five general physiological roles: bone and membrane structure (calcium, phosphorus, magnesium, fluoride); water and electrolyte balance (sodium, potassium, chloride); metabolic catalysis (zinc, copper, selenium, magnesium, manganese, molybdenum); oxygen binding (iron); hormone effects (iodine, chromium). While some of these functions are effected by the mineral ions themselves, many are effected by macromolecules in which one or more minerals are bound, either covalently or otherwise. Because these are all critical life functions, the tissue levels of many nutritionally essential mineral elements tend to be regulated within certain ranges - this, despite varying levels of intake by homeostatic control of enteric absorption, tissue storage and/or excretion. The ability to orchestrate these several physiological processes to achieve homeostatic control of cellular access to such mineral elements is an important factor in ameliorating the effects of short-term dietary deficiencies or excesses.