Glossary

acidspar

definition: acidspar
A grade of fluorspar containing more than 98% CaF2 and no more than 1% SiO2. It is used as a feed material for the production of hydrofluoric acid.

allanite

definition: allanite
A sorosilicate group of minerals within the broader epidote group that contain a significant amount of rare earth elements occuring mainly in metamorphosed clay rich sediments and felsic igneous rocks. There are three minerals in the allanite group, each recognized as a unique mineral: allanite-(Ce), allanite-(La) and allanite-(Y), depending on the dominant rare earth element present, cerium, lanthanum or yttrium.

alloy

definition: alloy
A compound that consists of two or more metals, or metals with a nonmetal.

aeschynite

definition: aeschynite
A group of rare-earth, titanium, rarely niobium and tantalum oxide-hydroxide minerals which mostly contains the rare earth elements cerium, neodymium and yttrium; typically it is translucent displays reddish brown to light brown color in transmitted light.

apatite

definition: apatite
Apatite is a group of phosphate minerals, usually referring to hydroxyapatite, fluorapatite, chlorapatite and bromapatite. The primary use of apatite is in the manufacture of fertilizer. Apatite is occasionally found to contain significant amounts of rare earth elements and can be used as an ore for those metals.

automotive

definition: automotive
A wide range of companies and organizations involved in the design, development, manufacture, marketing, and selling of motor vehicles.

bastnaesite

definition: bastnaesite
A yellowish to reddish-brown fluorocarbonate mineral that is a source of rare earth elements.

bauxite

definition: bauxite
Bauxite, an aluminium ore, is the world's main source of aluminium. It consists mostly of the minerals gibbsite Al(OH)3, boehmite γ-AlO(OH) and diaspore α-AlO(OH), mixed with the two iron oxides goethite and haematite, the clay mineral kaolinite and small amounts of anatase TiO2.

bentonite

definition: bentonite
Absorbent aluminium phyllosilicate, essentially impure clay consisting mostly of montmorillonite. There are different types of bentonite, each named after the respective dominant element, such as potassium (K), sodium (Na), calcium (Ca), and aluminium (Al).

boron

definition: boron
A chemical element with symbol B and atomic number 5.

britholite

definition: britholite
A rare-earth phosphate found in carbonatites. It is one of the most abundant REE-bearing mineral phases, and it is typically found in nepheline syenites and in contact metasomatic rocks related to alkali syenites and granites. Two natural end-members are known, britholite-(Ce) (formerly lessingite) and britholite-(Y) (formerly abukumalite). Typically it is opaque; only in thin flakes it can be transparent and exhibits usually a brown, yellow-brown or blue color.

calcination

definition: calcination
A thermal treatment process in presence of air or oxygen applied to ores and other solid materials to bring about a thermal decomposition, phase transition, or removal of a volatile fraction.

calcite

definition: calcite
A carbonate mineral and the most stable polymorph of calcium carbonate (CaCO3). The other polymorphs are the minerals aragonite and vaterite. Calcite is mined extensively for a wide variety of uses ranging from lime (cement) to limestone and marble building stones and aggregates, agricultural supplements and optical calcite. The mineral is transparent to opaque and shows a wide range of colors including colorless or white, gray, yellow, green due to included minerals. It appears colorless in transmitted light.

calcium

definition: calcium
A chemical element with symbol Ca and atomic number 20.

carbonatite

definition: carbonatite
Carbonatites are intrusive or extrusive igneous rocks defined by mineralogic composition consisting of greater than 50 percent carbonate minerals.

catapleiite

definition: catapleiite
Catapleiite is a rather rare zirconium mineral. It forms in alkaline rocks and rare rocks known as agpaites which are igneous rocks of unusual concentrations. They are characterized by high concentrations of alkali metals especially sodium and low concentrations of silicon and aluminum. Catapleiite is transparent, translucent to opaque exhibiting a wide color range from colorless, white, light yellow to yellowish brown over pale brown to grayish blue and violet. It is colorless in thin section.

cerite

definition: cerite
A complex silicate mineral group containing cerium. The cerium and lanthanum content varies with the Ce rich species (cerite-(Ce)) and the La rich species (cerite-(La)). It is transluscent to opaque exhibiting colors ranging from clove-brown with a reddish tinge over pale lavender-brown to colorless in thin fragments.

cerium

definition: cerium
The most abundant of the earth rare elements. Cerium is critical in the manufacture of environmental protection and pollution-control systems, from automobiles to oil refineries. Cerium oxides, and other cerium compounds, go into catalytic converters and larger-scale equipment to reduce the sulfur oxide emissions. Cerium is a diesel fuel additive for micro-filtration of pollutants, and promotes more complete fuel combustion for more energy efficiency.

cheralite

definition: cheralite
A thorium, calcium, rare earth bearing monazite. This semitransparent, greenish brown mineral occurrs either disseminated in a kaolinized pegmatite dikes and surrounding kaolinized granite gneiss, alluvial or in carbonatites. The mineral is semitransparent and typically exhibits colors ranging from pale to dark green, honey-brown to yellow-brown. It is of pale green or pale brown color in transmitted light.

churchite

definition: churchite
A white, gray, colorless, primarily Y-dominant phosphate mineral, with minor amounts of La, Nd, and Er. It typically exhibits colorless to snow- white or smoke-gray colors and appears colorless in transmitted light.

corundum

definition: corundum
A crystalline form of aluminium oxide (Al2O3) with traces of iron, titanium and chromium.

crandallite

definition: crandallite
The term crandallite refers to a group of phosphate minerals in the crandallite group, including the rare earth bearing florencite member. Crandallite itself is formed by groundwater precipitation in sedimentary rocks and soils as a result of the breakdown of other phosphate minerals e.g. in pegmatites. Typically it is translucent and of yellow, white or gray color. It is colorless in thin section.

cristobalite

definition: cristobalite
A high-temperature polymorph of silica, i.e. having the same chemical formula SiO2 but a distinct crystal structure.

crucible

definition: crucible
A container that can withstand very high temperatures and is used for metal, glass, and pigment production as well as a number of modern laboratory processes.

crystallization

definition: crystallization
The process of formation of solid crystals precipitating from a solution, melt or more rarely deposition directly from a gas.

diatomaceous

definition: diatomaceous
Diatomaceous earth is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder.

diffractometer

definition: diffractometer
A diffractometer is an instrument for analyzing the structure of a usually crystalline material from the diffraction pattern produced when an X-ray beam interacts with it.

dolomite
definition:dolomite
Anhydrous carbonate mineral composed of calcium magnesium carbonate CaMg(CO3)2. The word dolomite is also used to describe the sedimentary carbonate rock, which is composed predominantly of the mineral dolomite. Dolomite is used as an ornamental stone, a concrete aggregate, a source of magnesium oxide and in the Pidgeon process for the production of magnesium. The mineral is transparent to translucent and shows a wide range of colors from colorless over white to yellow, brown and pale pink. It appears colorless in transmitted light.

dysprosium
definition:dysprosium
Dysprosium is a rare earth element that has a metallic, bright silver luster. Its physical characteristics can be greatly affected even by small amounts of impurities. Dysprosium is never found in nature as a free element, though it is found in various minerals, such as xenotime. Dysprosium is used in electronic components to make them smaller and faster.

elastomer
definition:elastomer
A polymer with viscoelasticity (having both viscosity and elasticity) and very weak inter-molecular forces, generally having low Young's modulus and high failure strain compared with other materials.

EMC
acronym of:epoxy moulding compounds
enamel
definition:enamel
A smooth, durable coating made of e.g. melted and fused glass powder.

eudialyte
definition:eudialyte
A somewhat rare, nine member ring cyclosilicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites. Its name alludes to its ready solubility in acid. Eudialyte is used as a minor ore of zirconium, it is translucent and typically of brown, yellow-brown, yellow, pink, rose-red, cherry-red or red color. It appears colorless in thin section.

europium
definition:europium
A rare earth element that offers exceptional properties of photon emission. When it absorbs electrons or UV radiation, the europium atom changes energy levels to create a visible, luminescent emission. This emission creates the perfect red phosphors used in color televisions and computer screens around the world. Europium is also used in fluorescent lighting, which cuts energy use by 75% compared to incandescent lighting. In the medical field, europium is used to tag complex biochemical agents which helps to trace these materials during tissue research.

euxenite
definition:euxenite
A brownish black oxide mineral with a metallic luster which is usually opaque and translucent on thin edges. It occurs in granite pegmatites and detrital black sands and is used as an ore of the rare earth elements, rare large crystals have also been used in jewelry. It exhibits black, brownish black or greenish black color and appears brown to yellow-brown in transmitted light.

evaporation
definition:evaporation
A type of vaporization of a liquid that occurs from the surface of a liquid into a gaseous phase that is not saturated with the evaporating substance.

feldspar
definition:feldspar
A group of rock-forming tectosilicate minerals which make up as much as 60% of the earth's crust. Feldspar is a common raw material used in glassmaking, ceramics, and to some extent as a filler and extender in paint, plastics, and rubber.

fergusonite
definition:fergusonite
A mineral comprising a complex oxide of various rare earth elements. Yttrium is usually dominant, but sometimes Ce or Nd may predominate in molar proportion. The mineral is opaque, transparent on thin edges and exhibits gray, yellow, brown or brownish black color. It appears light brown to dark brown in transmitted light.

florencite
florencite
A mineral composed of basic phosphate of cerium and aluminum which is transparent to translucent. It shows a color range from pale yellow to butterscotch-yellow, red-orange, pink, pale brown, colorless to gray. It appears colorless to pale yellow in thin section and may be zoned. This reddish yellow mineral occurrs as a weathering product, typically of apatite, in highly argillized igneous rocks, bauxite, saprolite, carbonatites.

flotation
definition:flotation
Flotation is a mineral separation process, which takes place in a water-mineral suspension. Froth flotation is used for selectively separating minerals by taking advantage of differences in their hydrophobicity.

fluocerite
definition:fluocerite
A cerium, lanthanum fluoride mineral which is semitransparent. It exhibits a pale greenish to yellow color. It is recognized as two different minerals depending on the predominant REE cation, fluocerite-(Ce) and fluocerite-(La). Both crystallize in the hexagonal system.

fluorine
definition:fluorine
Extremely reactive and poisonous chemical element with atomic number 9.

fluorspar
definition:fluorspar
Fluorite (also called fluorspar) is a mineral which belongs to the halide minerals. Fluorite is a major source of hydrogen fluoride, a commodity chemical used to produce a wide range of materials. It is transparent to translucent and exhibits a wide color range from colorless, white purple, blue, green, yellow, orange over red, pink, brown to bluish black and is commonly zoned. In transmitted light it appears colorless.

gadolinite
definition:gadolinite
A silicate mineral which consists principally of the silicates of cerium, lanthanum, neodymium, yttrium, beryllium, and iron. Gadolinite is fairly rare and typically occurs as well-formed crystals. It is opaque, nearly transparent in thin fragments. Colour: black, greenish black, brown; grass-green to olive-green in thin fragments and has a vitreous luster. Gadolinite and euxenite are quite abundant and are future sources of yttrium sub group rare earths.

gadolinium
definition:gadolinium
A rare earth element with unique magnetic behavior. Thus this element is at the heart of magneto-optic recording technology, and other technology used in handling computer data.

gneiss
definition:gneiss
A common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks.

graphene
definition:graphene
Pure carbon in the form of a monatomic, nearly transparent sheet. Single graphene layers, which do form stacks building up naturally occuring graphite, have unique physical properties in terms of conductivity, strength, transparency and flexibility.

graphite
definition:graphite
A very common mineral, soft native carbon, occurring in black to dark-gray foliated masses, with metallic luster and greasy feel. Usually it is opaque but can be transparent in extremely thin flakes. It exhibits iron-black to steel-gray color and appears deep blue in transmitted light. Natural graphite is mostly consumed for refractories, batteries, steelmaking, expanded graphite, brake linings, foundry facings and lubricants.

heavy mineral sands
definition:heavy mineral sands
A class of ore deposit which is an important source of zirconium, titanium, thorium, tungsten, rare earth elements, the industrial minerals diamond, sapphire, garnet, and occasionally precious metals or gemstones.

hectorite
definition:hectorite
A rare soft, greasy, white clay mineral. Hectorite is mostly used in making cosmetics, but has uses in chemical and other industrial applications, and is a mineral source for refined lithium metal.

HREE
acronym of:heavy rare earth elements (Y, Sc, Gd-Lu)
Heavy rare earth elements (HREE) are the fraction of REE from gadolinium to lutetium accompanied by yttrium and scandium.

ilmenite
definition:ilmenite
It is an iron titanium oxide (FeTiO3) mineral with weakly magnetic properties. It is opaque and exhibits an iron-black to gray color with a brownish tint in reflected light. Most ilmenite is mined for titanium dioxide production.

ion exchange
definition:ion exchange
A reversible chemical reaction between an insoluble solid and a solution during which ions may be interchanged.

jadarite
definition:jadarite
A very rare white, earthy monoclinic silicate mineral that is relatively hard but very small grained. Jadarite contains boron and lithium, two valuable elements that are used in many applications e.g. in batteries or pharmaceutical industry.

kaolin
definition:kaolin
Kaolin is a soft, earthy, usually white mineral, produced by the chemical weathering of aluminium silicate minerals like feldspar. Kaolin is used in ceramics, medicine, coated paper, as a food additive in toothpaste, as a light diffusing material in white incandescent light bulbs, and in cosmetics. It is generally the main component in porcelain.

lanthanum
definition:lanthanum
A rare earth element that is extracted from the minerals bastnaesite and monazite via “solvent extraction”. Lanthanum is a strategically important rare earth element due to its activity in catalysts that are critical in petroleum refining. By one estimate, lanthanum “cracking-agents” increase refinery yield by as much as 10%, while reducing overall refinery power consumption.

lateric deposits
definition:lateric deposits
The ore, referred to as REE bearing ionic adsorption clay, mostly comes from two districs in the Jiangxi Province, Lognan and Xunwu, the former yielding exceptional HREE- and yttrium-rich material and the other, LREE-rich material.

laterite
definition:laterite
Soil types rich in iron and aluminum, formed in hot and wet tropical areas during intense and long-lasting weathering of the underlying parent rock. Nearly all laterites are rusty-red because of iron oxides.

lepidolite
definition:lepidolite
A lilac-gray or rose-colored phyllosilicate mineral of the mica group that is a secondary source of lithium. It is associated with other lithium bearing minerals like spodumene in pegmatite bodies. It is also one of the major sources of the rare alkali metals rubidium and caesium. Lepidolite occurs in granite pegmatites, in some high-temperature quartz veins, greisens and granites.

lime
definition:lime
A typically semitransparent calcium-containing inorganic material in which carbonates, oxides and hydroxides predominate which is typically colorless. Lime used in building products is broadly classified as pure, hydraulic, and poor lime can be natural or artificial, and may be further identified by its magnesium content such as dolomitic or magnesium lime.

limestone
definition:limestone
A sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3).

lithium
definition:lithium
A soft, silver-white metal that belongs to the alkali metal group of chemical elements. Because of its high reactivity, lithium never occurs in its elemental form in nature, and instead, only appears in compounds. Lithium occurs in a number of pegmatitic minerals, but is also commonly obtained from brines and clays. On a commercial scale, lithium is isolated electrolytically from a mixture of lithium chloride and potassium chloride. Main application fields of lithium are ceramics and glass, lithium-ion batteries and lubricating greases.

lithium carbonate
definition:lithium carbonate
A chemical compound of lithium, carbon, and oxygen. This colorless salt is widely used in the processing of metal oxides and has received attention for its use in psychiatry.

loparite
definition:loparite
Loparite-(Ce) is a granular, brittle oxide mineral of the perovskite class. It is black to dark grey and may appear grey to white in reflected light.

LREE
acronym of:light rare earth elements (La-Eu)
Light rare earth elements (LREE) are the light fraction of the REE from lanthanum to europium.

magnesium
definition:magnesium
A chemical element with the symbol Mg and atomic number 12.

metallurgy
definition:metallurgy
The science of extracting metals from their ores, purifying and alloying metals and creating useful objects from metals. The study of metals in bulk and at the atomic level.

metspar
definition:metspar
Metspar is also known as fluorspar, calcium fluoride, fluorite, crystalline calcium fluoride, fluorspar. It is transparent to translucent and typically ranges from colorless, white purple, blue, green, yellow, orange to red, pink, brown or bluish black depending on coloring trace elements. The mineral is commonly zoned. In transmitted light it appears colorless, but may be colored in thick sections.

mica
definition:mica
The mica group of sheet silicate (phyllosilicate) minerals includes several closely related materials having close to perfect basal cleavage. The commercially important micas are muscovite and phlogopite, which are used in a variety of applications.

monazite
definition:monazite
A reddish-brown phosphate mineral that contains rare earth elements.

neodymium
definition:neodymium
A rare earth element that is a critical component of strong permanent magnets. Cell phones, portable CD players, computers and most modern sound systems would not exist in their current form without the use of neodymium magnets. Neodymium-Iron-Boron (NdFeB) permanent magnets are essential for miniaturizing a variety of technologies. These magnets maximize the power/cost ratio, and are used in a large variety of motors and mechanical systems.

niobium
definition:niobium
A chemical element with the symbol Nb (formerly Cb) and atomic number 41.

ore
definition:ore
A rock that contains minerals bearing elements of economic value in economic concentrations that can be extracted by processing.

organophosphate
definition:organophosphate
General name for esters of phosphoric acid.

oxalate
definition:oxalate
Any salt or ester of oxalic acid, occurring in plants, especially spinach, rhubarb, and certain other vegetables and nuts, and capable of forming an insoluble salt with calcium and interfering with its absorption by the body.

oxide
definition:oxide
An oxide is any compound of oxygen with another element or radical.

parisite
definition:parisite
A rare mineral consisting of cerium, lanthanum and calcium fluoro-carbonate, Ca(Ce,La)2(CO3)3F2. The crystals are transparent to translucent. Its color ranges from brownish yellow, orange, orange-brown, brown to wax-yellow, grayish yellow or lilac. In transmitted light it appears colorless to yellow.

pegmatite
definition:pegmatite
A very coarse-grained intrusive igneous rock composed of interlocking grains usually larger than 2.5 cm size. Most pegmatites are composed of quartz, feldspar and mica. Pegmatites often contain rare earth minerals and gemstones, such as aquamarine, tourmaline, topaz, fluorite, apatite and corundum. They are also the primary source of lithium either as spodumene, lithiophyllite or usually from lepidolite (Li-mica).

petalite
definition:petalite
Petalite, also known as castorite, is a lithium aluminium tectosilicate mineral, crystallizing in the monoclinic system. It occurs in lithium bearing pegmatites with spodumene, lepidolite, and tourmaline. Petalite is an important ore of lithium, and is converted to spodumene and silica by roasting.

phosphorus
definition:phosphorus
A nonmetallic chemical element with symbol P and atomic number 15.

placer deposits
definition:placer deposits
An accumulation of valuable minerals formed by gravity separation during sedimentary processes.

polylithionite
definition:polylithionite
A transparent phyllosilicate mineral composed of potassium lithium aluminum silicate fluoride. Its color ranges from bright to pale pink, cream to white, colorless, pale brown to yellow-brown, bluish to greenish. In transmitted light it appears colorless. The pearly, transparent mineral occurrs in irregular segregations and veinlets, as a late-stage and metasomatic replacement mineral, in syenite pegmatites in a differentiated alkaline massif.

polymetallic Iron-Niobium-REE
definition:polymetallic Iron-Niobium-REE
The world largest REE source (Bayan Obo, China) is a giant polymetallic Iron-Niobium-REE deposit now regarded as a hydrothermal carbonate replacement, formed within sedimentary rocks (shale and marble) during a duration of 150 Mio years.

polystyrene
definition:polystyrene
A synthetic aromatic polymer made from the monomer styrene, a liquid petrochemical.

polytetrafluoroethylene
definition:polytetrafluoroethylene
A synthetic fluoropolymer of tetrafluoroethylene that has numerous applications.

polyurethane
definition:polyurethane
A polymer composed of a chain of organic units joined by carbamate (urethane) links.

potash
definition:potash
Any of various mined and manufactured salts that contain potassium in water-soluble form.

potassium
definition:potassium
A chemical element with symbol K (from Neo-Latin kalium) and atomic number 19.

ppm
abbreviation of:ppm
parts per million

praseodymium
definition:praseodymium
This rare earth element comprises at most 4% of the lanthanide content of bastnaesite, but is used as a common coloring pigment. Along with neodymium, praseodymium is used to filter certain wavelengths of light. So praseodymium finds specific uses in photographic filters, airport signal lenses, welder’s glasses, as well as broad uses in ceramic tile and glass (usually yellow). When used in an alloy, praseodymium is a component of permanent magnet systems designed for small motors. Praseodymium also has applications in internal combustion engines, as a catalyst for pollution control.

prosthetics
definition:prosthetics
A prosthesis is an artificial device that replaces a missing body part, which may be lost through trauma, disease, or congenital conditions.

pyrochlore
definition:pyrochlore
A solid solution between the niobium end member (pyrochlore) and the tantalum end member (microlite). Pyrochlore occurs in pegmatites associated with nepheline syenites and other alkalic rocks. It is also found in granite pegmatites and greisens. It is characteristically found in carbonatites.

quartz
definition:quartz
A colorless mineral often tinted by impurities, found in igneous, sedimentary, and metamorphic rocks. Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. Quartz is one of the most widely used natural materials. Its usefulness can be linked to its physical and chemical properties. Quartz is transparent to nearly opaque and due to a wide range of imupirities and mineral inclusions its colors range from colorless, white, rose-pink to rose-red, yellow to yellowish brown, green, blue, bluish violet, brown to black. It is often zoned or mottled.

quartzite
definition:quartzite
A hard, non-foliated metamorphic rock which was originally pure quartz sandstone. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of iron oxide (Fe2O3). Quartzite is becoming more popular as a dimension stone in the construction industry. The use of quartzite as decorative stone in building construction is growing annually.

rare earth minerals
definition:rare earth minerals
Well known minerals that contain REE include bastnaesite, monazite, xenotime, loparite, eudialyte, steenstrupin, euxenite, florencite, allanit, ancylite, parisite, cheralite, birtholite, apatite, ceranite and many more.

REE
acronym of:rare earth elements
Rare earth elements are a continuous series of 15 metallic elements known as the lanthanides plus scandium and yttrium.

refractory
definition:refractory
A refractory material is one that retains its strength at high temperatures.

REM
acronym of:rare earth metals
REO
acronym of:rare earth oxides
Rietveld
definition:Rietveld analysis
The Rietveld method is a technique used in powder diffraction analysis to refine structural models and quantify crystalline phases by fitting a theoretical line profile to the observed profile using a least squares refinement approach.

rutile
definition:rutile
A mineral composed primarily of titanium dioxide, TiO2 . It is typically opaque, but can be transparent in thin fragments. It exhibits a wide range of colors ranging from reddish brown, red, pale yellow, pale blue, violet to grass-green black if high in Nb-Ta; red to brownish red, pale yellow in transmitted light, deep brown to green. In reflected light it appears gray with bluish tint, with white, yellow and shows red internal reflections. Rutile has among the highest refractive indices at visible wavelengths of any known crystal, and also exhibits a particularly large birefringence and high dispersion. The main uses for rutile are the manufacture of refractory ceramic, as a pigment, and for the production of titanium metal.

scandium
definition:scandium
Scandium is number 21 on the periodic table of elements. It is considered a rare earth element but is not part of the lanthanide series. It is used to produce high performance materials in both the aerospace and sporting goods industries. It is also used in lighting, lasers and consumer electronics.

silica
definition:silica
Silica - also know as silicon dioxide - is an oxide of silicon with chemical formula SiO2. It has been known for its hardness since antiquity. Silica is most commonly found in nature as sand or quartz, as well as in the cell walls of diatoms. Silica is used primarily in the production of glass for windows, drinking glasses, beverage bottles, and many other uses. The majority of optical fibers for telecommunications are also made from silica. It is a primary raw material for many whiteware ceramics such as earthenware, stoneware and porcelain.

silicate
definition:silicate
A compound containing an anionic silicon compound. The great majority of silicates are oxides, but hexafluorosilicate ([SiF6]2-) and other anions are also included.

silicon
definition:silicon
Silicon is a chemical element with the symbol Si and atomic number 14, it is a tetravalent metalloid.

silicon carbide
definition:silicon carbide
A compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass-produced since 1893 for use as an abrasive.

sodium carbonate
definition:sodium carbonate
A sodium salt of carbonic acid (soluble in water). It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. The manufacture of glass is one of the most important uses of sodium carbonate.

spodumene
definition:spodumene
A pyroxene mineral consisting of lithium aluminium inosilicate. It occurs as colorless to yellowish, purplish, or lilac kunzite, yellowish-green or emerald-green hiddenite, prismatic crystals, often of great size. Spodumene is an important source of lithium for use in ceramics, mobile phone and automotive batteries, medicine and as a fluxing agent. Lithium is extracted from spodumene by fusing in acid.

steenstrupine
definition:steenstrupine
A mineral consisting of a complex silicate, phosphate, and fluoride of the rare-earth metals, calcium, sodium, aluminum, iron, and manganese, and occurring in dark brown rhombohedral crystals . It is opaque and exhibits brownish red to black color.

sulphate
definition:sulphate
A polyatomic anion. Sulfate is the spelling recommended by IUPAC, but sulphate is used in British English. Salts, acid derivatives, and peroxides of sulfate are widely used in industry.

synchysite
definition:synchysite
A group of carbonate minerals. Synchisite is related to parisite and consisting of a fluoride and carbonate of calcium, cerium, and lanthanum. It is a translucent mineral of wax-yellow, brown, to grayish yellow color. It appears colorless to pale yellow in transmitted light.

tantalum
definition:tantalum
A chemical element with the symbol Ta and atomic number 73.

technical ceramics
definition:technical ceramics
Technical ceramics are also known as engineering, advanced, special, and in Japan, fine ceramics. Such items include tiles used in the Space Shuttle program, gas burner nozzles, ballistic protection, nuclear fuel uranium oxide pellets, biomedical implants, coatings of jet engine turbine blades and missile nose cones.

terbium
definition:terbium
A rare earth element used in energy efficient fluorescent lamps. There are various terbium metal alloys that provide metallic films for magneto optic data recording.

thorium
definition:thorium
A soft silvery-white tetravalent radioactive metallic element, isotope 232, that is used as a power source in nuclear reactors. Thorium is present in the phosphate mineral monazite and in silicate and oxide minerals such as e.g. allanite and thorianite.

USGS
acronym of:United States Geological Survey
X-ray diffraction
definition:X-ray diffraction
X-ray diffraction is a non-destructive method used to probe crystalline structures at the atomic level. It can be used to determine arrangement of the atoms within a crystal and to identify crystalline phases.

xenotime
definition:xenotime
A rare earth phosphate mineral, whose major component is yttrium orthophosphate. The rare earths dysprosium, erbium, terbium, and ytterbium, and metal elements like thorium and uranium are the expressive secondary components of xenotime. Occurring as a minor accessory mineral, xenotime is found in pegmatites and other igneous rocks, as well as gneisses rich in mica and quartz.

yttrium
definition:yttrium
A rare earth element. Almost every vehicle on the road contains yttrium based materials that improve the fuel efficiency of the engine. Another important use of yttrium is in microwave communication devices. Yttrium- Iron- Garnets (YIG) are used as resonators in frequency meters, magnetic field measurement devices, tunable transistors and Gunn oscillators. Yttrium goes into laser crystals specific to spectral characteristics for high-performance communication systems.

zeolite
definition:zeolite
Microporous, aluminosilicate minerals commonly used as commercial adsorbents and catalysts. Zeolites occur naturally but are also produced industrially on a large scale. The color variations of zeolite range from an off-white/beige color to a light green.

zinnwaldite
definition:zinnwaldite
Potassium lithium iron aluminium silicate hydroxide fluoride is a silicate mineral in the mica group. Typically it is transparent to translucent and exhibits gray-brown, yellow-brown, pale violet to dark green color with color zoning being common. Its color ranges from colorless to light brown in thin section. It occurs in greisens, pegmatite, and quartz veins often associated with tin ore deposits. It is commonly associated with topaz, cassiterite, wolframite, lepidolite, spodumene, beryl, tourmaline, and fluorite.

zircon
definition:zircon
A mineral belonging to the group of nesosilicates. The natural color of zircon varies between colorless, yellow-golden, red, brown, blue, and green. Zircon is ubiquitous in the earth's crust. It occurs in igneous rocks, in metamorphic rocks and in sedimentary rocks. Zircon is mainly consumed as a opacifier in the decorative ceramics industry.

zirconia
definition:zirconia
Zirconium dioxide (ZrO2), sometimes known as zirconia (not to be confused with zircon), is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the mineral baddeleyite. A dopant stabilized cubic structured zirconia, cubic zirconia, is synthesized in various colours for use as a gemstone and a diamond simulant.

zirconosilicate
definition:zirconosilicate
A chemical compound, a silicate of zirconium. Zircon is a mineral belonging to the group of nesosilicates. Zircon is mainly consumed in the refractory industries, as an opacifier, and has been known to be used in the decorative ceramics industry.