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Industrial Minerals (IM) are natural minerals and rocks used as raw materials or functional additives in a wide range of manufacturing and other industries.
The main ones are: calcium carbonate, borate, kaolin, bentonite, feldspar, silica, and talc. 
Bentonite
Bentonite is a plastic clay that results from the in situ alteration of volcanic ash, and consists essentially of montmorillonite. Bentonite presents strong colloidal properties and increases its volume several fold when in contact with water, creating a gelatinous and viscous substance.
The special properties of bentonite (hydratation, swelling, water absorption, viscosity, thixotropy) make it a very valuable clay for a wide spectrum of uses, ranging from heavy industrial palletizing and foundry applications to consumer products such as cat litter and cosmetics.
Borate
The element borax doesn't occur by itself in nature but is typically found combined with oxygen, sodium, and calcium. Traces of these boron salts (i.e. borates) are present almost everywhere in rocks, soil and water. Large deposits of borates minerals include: trical, colemanite, hydroboracite, kermite, and alexite.
Borates are used in hundreds of products and processes in ways that touch the lives of almost everyone. Major uses include glass production, detergents, agriculture, enamels, and ceramic glazes. Apart from the industrial aspect, boron is an essential micronutrient, integral to a plant's life cycle and, as it becomes increasingly obvious, essential to animal life as well.
Calcium Carbonate
Industrial Calcium Carbonate (CaC03) is produced in two ways: by extraction/milling of natural ore (Ground Calcium Carbonate-GCC), and by chemical precipitation (Precipitated Calcium Carbonate -PCC).
The suitable ore-bodies for producing GCC include chalk, limestone, marble, and travertine. Sufficiently pure ore-bodies are selected to allow direct exploitation. PCC is produced as a by-product of caustic soda synthesis or through a recarbonizing process. Both GCC and PCC fit to high-level specifications. Dolomite is a double carbonate of calcium and magnesium.
The main applications of GCC, PCC and dolomite include paper, paints, plastics, pharmaceuticals, etc.
Feldspar
Feldspar is by far the most abundant group of minerals in the earth's crust, forming about 60% of terrestrial rocks. The classification of a wide range of rocks is based on their feldspar content. Most frequently, commercial feldspar is mined from pegmatite, feldspatic sands or aplite deposits.
For some applications, the ore has to undergo processing in order to remove some accessory minerals (quartz, mica, etc.) while in other cases, their presence is advantageous.
The two main properties that make feldspar useful for industry are its alkali and aluminum content. Main applications include the ceramic and glass industries.
Kaolin
Kaolin is a purified white plastic clay primarily composed of kaolinite in association with small quantities of other minerals such as feldspar, mica and quartz. It is made up of a loose aggregation of randomly oriented stacks of kaolinite flakes.
Kaolin deposits are formed through the alteration, or kaolinisation of feldspar-rich rocks such as granite or gneiss by hydrothermal and/or weathering processes. The mineralogical and chemical composition of the kaolin depends on the nature of the parent rock and the type and degree of alteration.
Kaolin main applications include paper, in which it performs both filling and coating functions, and ceramics. In this latter application, it can account for as much as 60% of the recipe. Other applications include paint, rubber, plastics, pharmaceuticals, etc.
Silica
Crystalline silica is the name of a group of minerals composed of silicon and oxygen. The term crystalline refers to the fact that the silicon and oxygen atoms are arranged in a three-dimensional repeating pattern. The main minerals included in this group are: quartz, cristobalite and tridymite. Quartz is the most common of them and, after feldspar, is the second most abundant mineral on the Earth's surface.
Crystalline silica, basically in the form of quartz, has been mined for thousands of years. It is really one of the building blocks of ancient and current civilizations, being also vital for modern technologies.
Main applications include glass production, foundry, ceramics, building materials, etc. Crystalline silica has also acquired a fundamental place in the emerging information society, as the source of silicium.
Talc
Talc is our planet's softest mineral. It is a hydrated magnesium silicate that belongs to the phyllosilicate family. Although all talc are lamellar, chemically inert, organophylic and water-repellent to a greater or lesser degree, no two talc are quite the same. A talc's lamellarity for instance depends upon the conditions that prevailed during the formation of the deposit. Small crystals provide a compact, dense ore whilst large crystals come in papery layers.
Talc is always found in combination with at least one other mineral and the type and quantity of by-minerals is also a distinguishing factor. The most common of these is chlorite which is chemically and structurally very similar to talc. Dolomite and magnesite are also often present.
Each talc's unique properties confer specific functions to a wide range of products and processes including paint, polymers, paper, ceramics, animal feed, rubber, roofing, fertilizers, cosmetics, pharmaceuticals.
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