Coal is the best answer. Coal is primarily used in generating electricity. It is also a good source of raw materials for making heating oils, chemicals and medicines. Bauxite on the other hand is the mineral ore of aluminum which is used in the manufacture of cans, airplanes, sporting and electronic equipment and home appliances. Halite is commonly recognized as salt and is used in human and animal diet, food seasoning and food preservation. Lastly, limestone is used as dimension stone in buildings and as a component of cement.