A Brief and Simplified Mineral Typology by Characteristics and Uses
By Lyman Mlambo
There are a variety of minerals out there. One useful way of classifying them is by their use. Incidentally minerals sharing similar uses tend to have similar characteristics, especially in terms of bulkiness, abundance in the earth’s crust and unit value. This article presents a brief classification of minerals and uses of the various specific minerals. Minerals are classified into building materials, industrial minerals, metallic minerals, precious stones, and mineral fuels.
Building materials are used for various forms of construction work ranging from dams, roads, to houses. They are characterized by the following: (i) are normally bulk – occurring in large reserves and supply; (ii) are geologically common; (iii) are easily substitutable in use among themselves; (iv) need little processing; (v) have low unit prices; (vi) have high costs of transport; (vii) their exploration, mining and processing are relatively inexpensive; and (viii) are used in construction work in substantial quantities. Examples include sand, gravel, stone, crushed rock, clay-rich rock, limestone (as raw material for cement manufacturing) and black granite.
Industrial minerals are mainly used as fertilizers or as raw materials in industrial processes (for example, in the chemical industry, or industries making abrasives, etc.). Like building materials, they are non-metallic, geologically abundant, require little processing before use, and are supplied and used in large quantities. Examples are phosphates, limestone, magnesite, and asbestos. The similarity in characteristics between building materials and industrial minerals implies similarity or intersection in usage. For example, limestone can be used for cement and agricultural lime, asbestos can be used for roofing and for friction products and magnesite is used in agricultural, chemical and construction industries (see Table 1). These minerals are therefore both building materials and industrial minerals.
Metallic minerals are precious metals (gold, silver, and PGMs), base metals (copper, lead, zinc, tin, et cetera), light metals (aluminium, magnesium, and titanium), iron and steel alloys (manganese, vanadium, tungsten, nickel, cobalt, chromium and molybdenum), and fuel metals (thorium and uranium).They: (i) are less abundant; (ii) are less uniformly or regularly distributed in the earth’s crust; (iii) require significant processing before use; (iv) have costly mining and processing operations; and (v) easily render themselves to recycling. A simple business dictionary definition of base metal, however is “Relatively inexpensive and common metal … that (unlike noble metals such as gold, silver, or platinum) corrodes and/or tarnishes when exposed to air or moisture” (WebFinance Inc., 2016a).
The Oxford University Press (2016) defines a precious stone as “A highly attractive and valuable piece of mineral, used especially in jewellery; a gemstone”. Common examples of precious stones are diamonds and emeralds. Note that among diamonds is a type that is industrial and not gem-quality, which finds application in industry; for example, in making diamond drilling bits and abrasive materials (see Table 1). Thus, this type may be termed an industrial mineral, further confirming that these classes are not really hard and fast, though expedient. There are also semi-precious stones like tourmaline, aquamarine, chrysoberyl, topaz, alexandrite, et cetera (Mugandani & Masiya, 2011).
Mineral fuels include nuclear fuels (uranium and thorium), and fossil fuels (tar sand, oil shale, coal, petroleum, natural gas and coal-bed methane gas). Coal, petroleum, natural gas and coal-bed methane gas are also termed hydrocarbons. A hydrocarbon is an “Organic compound (such as benzene, methane, paraffin) made of two elements carbon and hydrogen and found in coal, crude oil, natural gas, and plant life. Hydrocarbons are used as fuels …” (WebFinance, Inc.,2016b). Note that nuclear fuels are also termed fuel metals because they are like metals in terms of their geologic occurrence.
Table 1: Some Common Minerals and their Major Uses
|Diamonds||Diamond drilling bits; abrasive materials; jewelry|
|Gold||Dentistry; Computer hardware, communication equipment, space/aircraft engines, etc (due to electrical conductivity); Financial uses e.g. backing of currency; Jewelry|
|Platinum||Chemical catalysts used in oil refineries, gasoline production and petrochemical products; Oxidation catalysts in catalytic convertors to treat automobile exhaust emissions; Alloys used in furnace components; Jewelry|
|Chrome||Production of stainless steel; Catalyst; Plating; Pigments|
|Nickel||Coinage; Rechargeable batteries; Super-alloys used in combustion turbines in power generation; Refined metal; Ferronickel; Catalysts; Plating|
|Copper||Major industrial metal ranking third after iron and aluminum; Power transmission; Power generation; Building construction (single largest use); Telecommunications; Plating|
|Iron ore||Iron and steel industries|
|Lithium||Heat resistant glass; Ceramics; Greases; Batteries; Neurological drug for mood stabilization|
|Tantalite||Lamp filament (now substituted by tungsten); Construction of chemical process plants; Electronic components (tantalum capacitators in mobile phones, computer components – memory chips, in automobiles)|
|Asbestos||Fibre for electrical insulation and textiles; Roofing products; Gaskets; Friction products|
|Graphite||In high temperature lubricants; Friction materials; Battery and fuel cells|
|Limestone||Cement; Agricultural lime|
|Magnesite||Source of magnesium used in agricultural, chemical and construction industries|
|Coal||Steam coal – power generation; Cooking; Coking coal used in steel production|
|CBM||Generation of electricity generation, gas, diesel, petrol and ethanol|
Source: USGS Website(Lyman Mlambo is the Executive Director of LMS Mining Consultancy. This article is a direct extract, with small changes, of Section 2.4 from the author’s report on “Extractives and Sustainable Development II: Minerals, Oil and Gas Sectors in Zimbabwe”, which was funded and published by the Friedrich Ebert Stiftung Zimbabwe in 2018. For details on any references in the article kindly contact the author through email@example.com)