Earth Materials Introduction to Mineralogy and Petrology

In four prior chapters that deal with systematic aspects of minerals (Chapters 7, 11, 14, and 16) each discussion begins with occurrence and ends with uses. The paragraphs on occurrence dealt mainly with the types of rocks in which a specific mineral occurs most commonly, and under uses we listed some of the most important applications of that same mineral. Here, we give a few brief descriptions of some mineral and ore deposits that are the source of rocks, minerals, and chemical elements commonly used in everyday life.

A mineral deposit is a concentration of minerals that was formed by geologic processes. An ore deposit is a geologic occurrence of minerals (and chemical elements) from which minerals (or elements) of economic value can be extracted at a reasonable profit. Our most basic essential resources are water and soil.

It is instructive to assess what materials you are surrounded by in your own house that are the result of mining of Earth materials and their subsequent transformation into metals (or alloys and other materials) used in the house. The house's foundation, or basement, is probably poured concrete, which consists of an aggregate of sand and gravel in Portland cement. Steel beams that support the structure are derived from iron ore, which consists mainly of hematite, magnetite, and/or goethite. The brick, drain pipes, and roof tiles are made from common kaolinitic clays and shales. The ceramic products such as bathroom toilets, sinks, and wall tiles are made from essentially pure white kaolin clays. So is the chinaware in the kitchen cabinets. The stainless steel cooking pots and utensils, as well as kitchen and bathroom fixtures, are made of various metal alloys, and much of the plumbing and all electrical wiring is made of copper. There may be aluminum frames around windows, the glass of which is the product of high-temperature melting in furnaces of pure quartz sands. The kitchen and bathroom counters may be fitted with dimension stone, such as granite or marble. Even the gems and gold used for adornment are extracted from the Earth. The fertilizer used in the yard, consisting of various ratios of P2O5, K2O, and S, is extracted from apatite, sylvite, and native sulfur, respectively.