Note that our rather exact definition of what a mineral is excludes many of the everyday meanings of the word "mineral". for instance, to some a "mineral resource" can be substance, such as stone, coal, petroleum, gravel, salt, or diamond, that is extracted from the ground and sold as a commodity. to a nutritionist, minerals are the inorganic elements found in foods, like iron and potassium and calcium, that are essential to life. in popular speech, any substance that is neither "animal" nor "vegetable" is "mineral". discuss why any of these definitions do not necessarily meet the requirements of the definition used by geologists.