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Measure of the roughness due to the kaolin particle shape and size and the presence of quartz.

A compound that adheres or bonds two items together. Adhesives may come from either natural or synthetic sources.

A mineral (aluminium oxide [Al2O3]) usually found in the clay used for brick making; also used as a ceramic substrate material.

Aluminium silicate
(Or aluminum silicate) has the chemical formula Al2SiO5. It has a density of 2.8 to 2.9 g/cm³, a vitreous lustre, a refractive index of 1.56, a Mohs hardness of 1-2, and an orthorhombic crystal


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Antiblock additive
An antiblock additive is a mineral that creates a small ammount of surface roughness in a film to stop it sticking to itself.

Ball clay
Kaolinitic sedimentary clays, that commonly consists of 20-80% kaolinite, 10-25% mica, 6-65% quartz.

Breathable film
A polyolefin film into which coated ground calcium carbonate (Filmlink™) is incorporated during the production process. This creates micropores that allow air to circulate without affecting the film’s watertightness.

The reflectance (or whiteness) of the dried kaolin.  Enhanced by the  removal of coloured contaminants to improve the whiteness of the kaolin product.

A thermal treatment process applied to ores and other solid materials in order to bring about a thermal decomposition, phase transition, or removal of a volatile fraction. The calcination process normally takes place at temperatures below the melting point of the product materials. Calcination is to be distinguished from roasting, in which more complex gas-solid reactions take place between the furnace atmosphere and the solids, however calcination takes place in the absence of air.

Calcined kaolin
Kaolin modified through very high (700-1,200ºC) temperatures. Calcination improves whiteness and changes the chemistry, making the kaolin less hydrophilic and reducing electrical conductivity


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The chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust.

Calcium carbonate
A chemical compound, with the chemical formula CaCO3. It is a common substance found as rock in all parts of the world, and is the main component of shells of marine organisms, snails, and eggshells.

A chemical element with the symbol C and atomic number 6. It is a group 14, nonmetallic, tetravalent element, that presents several allotropic forms of which the best known ones are graphite (the thermodynamically stable form under normal conditions), diamond, and amorphous carbon.

China clay
Also known as kaolin, is a white soft plastic clay derived from the decomposition of granite or similar rock. Most kaolin is wet refined to produce a range of products to improve both physical and chemical properties to meet specific customer applications. The Group has mineral reserves in all three high-quality kaolin mining regions in the world: Cornwall, UK; Georgia, USA; and the Amazon delta in Brazil.


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Common mineral or rock type consisting of carbonates of calcium, iron, and/or magnesium.

A process used to seal the seams in wooden boats or ships, and riveted iron or steel ships, in order to make them watertight. The same term also refers to the application of flexible sealing compounds to close up crevices in buildings against water, air, dust, insects, or as a component in firestopping.

The process of separating valuable minerals from impurities or separating minerals into different particle sizes.

A naturally occurring material, composed primarily of fine-grained minerals, which show plasticity through a variable range of water content, and which can be hardened when dried or fired.

Critical Pigment Volume concentration, the amount of pigment in a paint formulation at which the binder just covers all the pigment surface. The point at which several important paint properties change significantly

The (natural or artificial) process of formation of solid crystals from a uniform solution. Crystallization is also a chemical solid-liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid crystalline phase occurs.

Cultured marble
A mixture of resin and ground marble or limestone.


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Diatomite (Diatomaceous Earth)
A naturally occurring, soft, chalk-like sedimentary rock that is easily crumbled into a fine white to off-white powder, with a particle size extending from less than 1 to over 100 microns.

White powder deposited on the surface of concrete containing products, formed as a result of reaction between calcium hydroxide and atmospheric carbon dioxide.

A group of rock-forming minerals which make up as much as 60% of the Earth's crust. Feldspars crystallize from magma in both intrusive and extrusive rocks, and they can also occur as compact minerals, as veins, and are also present in many types of metamorphic rock.

Flexible Intermediate Bulk Container, typically holding 1 tonne of material

Particles added to a matrix material, usually to improve its properties

A medium to coarse-grained felsic intrusive rock which contains 10-50% quartz.  Granitoid is the generic or collective name for the many different kinds of felsic intrusive rock.


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Ground calcium carbonate (GCC)
Originates from the sedimentation of seashells and other marine life, which formed deep bands of chalk and limestone. Exposure to intense heat and pressure as continents shifted, recrystalised some of these into marble as seen in the renowned mountains of Carrara in Italy. Grinding these minerals gives products with a precise shape and size, characterized by their high brightness. Imerys has a global platform for the production of GCC with reserves in Europe, North America and South America, Asia.

Hard clay
A description of a clay that reinforces rubber compounds, giving a hard feeling rubber article

High Density Poly Ethylene

Kaolin ore which has been wet processed

Igneous rocks
Rocks formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.


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Also known as china clay, is a white soft plastic clay derived from the decomposition of granite or similar rock. Most kaolin is wet refined to produce a range of products to improve both physical and chemical properties to meet specific customer applications. The Group has mineral reserves in all three high-quality kaolin mining regions in the world: Cornwall, UK; Georgia, USA; and the Amazon delta in Brazil.

A common hydrous aluminium silicate mineral found in sediments, soils, hydrothermal deposits, and sedimentary rocks.  It is a member of the kaolin group of minerals with the chemical composition Al2Si2O5(OH)4.

Linear low-density polyethylene

A nonfoliated metamorphic rock resulting from the metamorphism of limestone, composed mostly of calcite (a crystalline form of calcium carbonate, CaCO3).

A dehydroxylated form of the clay mineral kaolinite

The mica group of sheet silicate minerals includes several closely related materials having highly perfect basal cleavage. All are monoclinic with a tendency towards pseudo-hexagonal crystals and are similar in chemical composition.


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High energy milling process to break up the kaolin agglomerates formed during drying.

A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties.

MS Sealant
Moisture sensitive sealant

A sub micron particle sized material

National Collegiate Athletic Association

A pigment that contibutes opacity or hiding power to a coating or film

The effect generated by an opacifier, the opposite of a clear coating or film

Particle size
A notion introduced for comparing dimension of various small material objects.


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Particle size distribution (PSD)
A determination of the distribution of the particles in a series of size classes of a soil, sediment or rock.

Precipitated Calcium Carbonate

An amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently. It is an industrial mineral and a commercial product useful for its light weight after processing.

Measurement of the acidity.

Parts per hundred, used in the plastics industry to describe the amount of each ingredient to the polymer.

The chemical name for the branded product Nylon

A thermoplastic commodity heavily used in consumer products.


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A thermoplastic polymer, made by the chemical industry and used in a wide variety of applications

A material which when combined with calcium hydroxide, gives cementitious properties. They can be industrial by-products such as fly ash or manufactured materials. Typically they contain vitreous siliceous material.

The use of high intensity mills to reduce the particle size of the minerals

Polyvinyl chloride

Mineral species composed of crystalline silica.

Principally concerned with extending the "classical" disciplines of elasticity and (Newtonian) fluid mechanics to materials whose mechanical behavior cannot be described with the classical theories.

Rheological properties
Rheology refers to the deformation and flow of matter. The rheological properties of a liquid are dominant features that can be quantified to characterise its behaviour its response to a forced shearing flow.   Quantitative parameters used are viscosity, elasticity, shear rate, shear strain, and shear stress.


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A viscous material that changes state to become solid, once applied, and is used to prevent the penetration of air, gas, noise, dust, fire, smoke or liquid from one location through a barrier into another.

Secondary clay
A clay which is removed from it's place of generation by erosion and deposited in another area with different geology, often significant distances away

Sedimentary rock
One of the three main rock groups (the others being igneous and metamorphic rock). Rock formed from sediments covers 75-80% of the Earth's land area, and includes common types such as chalk, limestone, dolomite, sandstone, conglomerate and shale.

A chemical (SiH4) used to modify the surface of kaolin particles so they are compatible with polymers.

Slurry or slurries
A dispersion of mineral in water, sometimes with dispersion aids and biocides added.

Soft clay
A description of a clay that does not offer significant reinforcement in rubber compounds

The property of some non-newtonian pseudoplastic fluids to show a time-dependent change in viscosity; the longer the fluid undergoes shear stress, the lower its viscosity.


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Titanium dioxide, also known as titanium(IV) oxide or titania

Toll processing
A service to produce materials to customer generated specifications.

Unplasticized polyvinyl chloride

The flow resistance of the kaolin slurry measured at various shear rates.

Physical disintegration and chemical decomposition of earthy and rocky materials on exposure to atmospheric agents, producing an in-place mantle of waste.


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