|
Mineral/rock |
Derived from or for |
|
Actinolite |
Greek actino = ray and lithos = stone in reference to its occurrence in bundles of radiating needles |
|
Agalmatolite |
Greek algalma = image and lithos = stone as it was carved by the Chinese |
|
Agate |
locality at the River Achates, now Drillo in Sicily, where it was originally found |
|
Aggregate |
Latin aggregatus = to lead to a flock, add to |
|
Akageneite |
locality at Akagame mine, Iwate Prefecture, Japan |
|
Alabandite |
locality at Alabanda in Caria, Asia Minor |
|
Alabaster |
ancient ointment jars called alabastra and perhaps Alabastron in Egypt; alternatively from Egyptian a-la-baste = ship of the Goddess Ebaste = Bubaste |
|
Albite |
Latin albus = white, for its color |
|
Alexandrite |
Czar Alexander II (1818-1881) of Russia |
|
Allanite |
Thomas Allan (1777-1833), Scottish mineralogist and first observer |
|
Almandine (garnet) |
Alabanda, Asia Minor, where garnets were cut and polished |
|
Aluminum |
Latin alumen = alum, original name for natural aluminum sulfate |
|
Alunite |
Latin alumen = alum (see above) and French alun = alum |
|
Amazonite |
locality at Amazon River, South America |
|
Amber |
French ambre from Arabic anbar = ambergris (now obsolete) |
|
Amblygonite |
Greek amblys = dull, obtuse and gonia = angle, in reference to cleavage angle |
|
Amethyst |
Latin amethystus and Greek amethystos = not drunken as the stone and plant was thought to orevent intoxication |
|
Amosite |
acronym of Asbestos Mines of South Africa |
|
Analcime |
Greek analkis = without strength due to its weak electrical properties when heated or rubbed |
|
Anatase |
Greek anatasis = extension because of the greater length of the common pyramid as compared with other tetragonal minerals |
|
Andradite (garnet) |
J.B.d’Andrada e Silva (1763-1838), Brazilian mineralogist and first observer |
|
Anhydrite |
Greek anhydros = dry or without water |
|
Anorthite |
Greek for not straight, because of its triclinic symmetry |
|
Antimony |
Latin from Greek anti = against plus monos = a metal seldom found alone |
|
Andalusite |
locality at Andalusia, Spain |
|
Anthophyllite |
neo-Latin anthophyllum = clove for its brown color, Greek lithos = stone |
|
Apatite |
Greek apate = deceit since it was often mistaken for other minerals |
|
Aphthitalite |
Greek aphthitos = unchangeable or indestructible, alis = salt, and lithos = stone since it is very stable in air |
|
Aquamarine |
Latin aqua marina = seawater alluding to its pale bluish-green color |
|
Aragonite |
locality at Aragon, Spain, where it was first identified |
|
Arcanite |
Medieval Latin alchemical name, Arcanum duplicatum = double secret |
|
Asbestos |
Latin and Greek asbestos = inextinguishable alluding to its early uses as a wick |
|
Ascherite |
a.k.a Szaibelyle |
|
Atacamite |
locality at Atacama Desert, Chile |
|
Attapulgite |
locality at Attapulgus, Georgia, USA |
|
Axinite |
Greek axine = ax in reference to its wedge-shaped crystals |
|
Azoproit |
Russian title for the International Association for the Study of Deep Zones of the Earth’s Crust (AZOPRO) since it was found during the preparation of a guidebook for the Association’s meeting in Baikal in 1969 |
|
Baddeleyite |
Joseph Baddeley who brought the original specimens from Sri Lanka |
|
Ball clay |
from the tradition of rolling the clay to the cart and thus forming a “ball” weighing 13-22 kg (30-50 lb) with a diameter of about 25 cm (10 inches) |
|
Barite |
Greek barys = heavy or dense |
|
Barylite |
Greek barys = heavy or dense, lithos = stone |
|
Bassanite |
locality at Basset group of mines, Redruth, Cornwall, England |
|
Bastnaesite |
locality at Bastnäs, Vastmanland, Sweden |
|
Bauxite |
locality at Les Baux, near Arles, France where it was discovered by P. Berthierin |
|
Beidellite |
locality at Beidell, Colorado |
|
Bementite |
Clarence Sweet Bement (1843-1923), American machine tool manufacturer from Philadelphia; collector of coins, books, and minerals |
|
Benstonite |
for O.J. Benston (1901- ), American ore dressing metallurgist, National Lead Company, Malvern, AR, who provided specimens for initial study |
|
Bentonite |
for the Benton Shale named for Fort Benton, Montana, United States (originally named Taylorite for Taylor Ranch, the site of the first mine near Rock River, Wyoming, which opened in 1888) |
|
Bertrandite |
Marcel Alexandre Bertrand (1847-1907), French mineralogist |
|
Beryl |
Greek beryllos of uncertain etymology applied to beryl and green gems |
|
Beryllium |
beryl (see above), the mineral from which it was isolated |
|
Bikitaite |
locality at Bikita, Zimbabwe |
|
Biotite |
Jean Baptiste Biot (1774-1862), French physicist who studied its optical aspects |
|
Birnessite |
locality at Birness, Scotland |
|
Bischofite |
Gustav Bischof (1792-1870), German chemist and geologist |
|
Bixbyite |
Maynard Bixby of Salt Lake City, UT, who compiled a catalog of Utah minerals |
|
Blanc fixe |
French blanc = white and fixe = settled referring to the barium sulfate precipitate |
|
Bloedite |
Carl August Bloede (1773-1820), German chemist |
|
Boehmite |
Johannes Böhm (1857-1938), German geologist and first observer |
|
Boracite |
derived from borax (see below). A.k.a. |
|
Borax |
Persian burah and Arabic buraq, both old names for the mineral. A.k.a. tincal. |
|
Bradleyite |
Wilmot Hyde Bradley (b. 1899), American geologist, USGS |
|
Brannerite |
John Casper Branner (1850-1922), American geologist |
|
Braunite |
Kammerath Braun, of Gotha, Germany |
|
Brazilianite |
Brazil, where the mineral was first found |
|
Bromine |
Greek bromos = stench in reference to its characteristic odor |
|
Bromargyrite |
Greek bromos = stench and argyros = silver alluding to to composition |
|
Brookite |
Henry James Brooke (1771-1857), English mineralogist |
|
Brucite |
Archibald Bruce (1777-1818), American mineralogist and first observer |
|
Brüggenite |
Juan Brüggen (1887-1953), Chilean geologist |
|
Burkeite |
William Edmund Burke (1980-), American chemical engineer |
|
Cahnite |
Lazard Cahn (1865-1940), American mineral collector who first recognized the mineral in Franklin, New Jersey. |
|
Cairngorm |
locality at Cairngorm, southwest of Banff, Scotland |
|
Calcite |
Latin calx, calcis = lime; this is the same origin for chalk and limestone |
|
Carnallite |
Rudolph von Carnall (1804-1874), Prussian mining engineer, Greek lithos = stone |
|
Celestite |
Latin caelestis = heavenly for its faint blue color |
|
Cement |
Old French ciment from Latin caementum = chip of stone used to fill up in building a wall |
|
Cerite/Cerium |
after Ceris, an asteroid discovered in 1803 |
|
Chabazite (zeolite) |
Greek chabazios or chalazios, an ancient name of a stone celebrated in a poem ascribed to Orpheus |
|
Chalcedony |
from Chalcedon or Calchedon, an ancient maritime city of Bithynia on the Sea of Marmara in modern Turkey |
|
Chalcophanite |
Greek chalcos = copper and to appear refering to the change of color on ignition |
|
Chalcopyrite |
Greek chalcos = copper and its similarity with pyrite. |
|
Chaistolite |
Greek chiastos = marked with a chi (x) and lithos = stone alluding to the cross exhibited in transverse sections |
|
China clay |
commercial term for kaolin which was named for Kau-ling in China |
|
Chiolite |
Greek = snow alluding to its appearance and similarity to cryolite (ice) |
|
Chlorite |
Greek chloros = light green in reference to its color |
|
Chromite |
Greek chroma = a color for the brilliant hues of its compounds |
|
Chrysoberyl |
Greek chrysos = golden or yellow plus beryllos = beryl |
|
Chrysolite |
Greek chrysos = golden or yellow plus lithos = stone |
|
Chrysoprase |
Greek chrysos = golden or yellow plus prason = leek alluding to green color |
|
Chrysotile |
Greek chrysotos = guilded in reference to its color and nature |
|
Citrine |
Latin citrus or French citron = lemon in reference to its yellow color |
|
Clinoenstatite |
Greek klinein = to bend or slope (monoclinic diomorph) of enstates = an adversary because of its refractory nature |
|
Clinoptilolite |
Greek klinein = to bend or slope, monoclinic Greek for wing or down alluding to its light nature, and lithos = stone |
|
Colemanite |
William Tell Coleman (1824-1893), a borate developer in California |
|
Cordierite |
Pierre Louis A. Cordier (1777-1861), French mining engineer & geologist |
|
Coronadite |
for Francisco Vasquez de Coronado (ca. 1500-1554), Spanish explorer of SW America |
|
Corundum |
Hindi kurund, or the Tamil kurundam, describing a native stone of India |
|
Crandallite |
Milan L. Crandell Jr., American engineer, Knight Syndicate, Provo, Utah and Greek lithos = stone |
|
Cristobalite |
Cerro San Cristóbal near Pachuca, Mexico and Greek lithos = stone |
|
Crocidolite |
Greek krokis or krokidos = the nap on cloth and lithos = stone |
|
Cryolite |
Greek kryos = cold, frost and lithos = stone for its icy appearance |
|
Cryptomelane |
Greek kryptos = hidden, secret and melas = black in reference to the difficulty of identifying it as a species and its color |
|
Danburite |
locality at Danbury, Connecticut |
|
D’ Ansite |
Jean D’ Ans (1881- ), German chemist, professor, Berlin |
|
Darapskite |
for Ludwig Darapsky (1857-?), mineralogist and chemist from Santiago, Chile |
|
Datolite |
Greek = to divide due to granular character of some varieties |
|
Dawsonite |
John William Dawson (1820-1899), Canadian geologist, principal of McGill University, Montreal, Canada |
|
Diamond |
Latin adamas = unconquerable or invincible; first used in Manilius (AD 16) |
|
Diaspore |
Greek dia = through and speirein = to scatter in reference to its characteristic decrepitation on heating |
|
Dickite |
Allan Brugh Dick (1833-1926), Scottish metallurgical chemist |
|
Diatomite |
Latin from Greek dia = through and tome = cutting in reference to the two generally symmetrical valves of the single-cell diatom |
|
Dietzeite |
August Dietze (?-1893?), who first described the mineral |
|
Diopside |
Greek diopsis = to view through since it is usually transparent |
|
Dolomite |
Deodat Guy Silvain Tancrède Gratet de Dolomieu, French geologist |
|
Dumortierite |
Eugène Dumortier (1802-1873), French paleontologist |
|
Dunite |
named for its type locality at Dun Mountain, Nelson, New Zealand |
|
Dysprosium |
Greek dysprositos = hard to get at in reference to the difficulty of separation |
|
Embolite |
Greek embole = insert and lithos = stone since it contains both the chloride and bromide of silver |
|
Emerald |
Latin smaragdus and Greek smaragdos = emerald, probably of Semitic origin; ancient name applied to a variety of green minerals |
|
Emery |
French emeri, Italian smeriglio, and Greek smiris or smeris; akin to the Greek myron = urgent |
|
Epsomite |
locality at Epsom, a town near London, England |
|
Erionite (zeolite) |
Greek erion = wool alluding to its white wool-like appearance |
|
Euclase |
Greek eu = good, well and klasis = a breaking due to its easy cleavage |
|
Eucryplite |
Greek eu = good, and concealed due to its mode of occurrence embedded in albite |
|
Eudialyte |
Greek eu = good, well and dialytos = capable of dissolution |
|
Eudidymite |
Greek eu = good, well and twin, due to the twinned crystal |
|
Eugsterite |
N.A. |
|
Europium |
Continent of Europe named for Europa, daughter of a king of Phoenicia |
|
Euxenite |
Greek for friendly to strangers or hospitable referring to the rare-earth elements it contains |
|
Faujasite (zeolite) |
Barthélemy Faujas de Saint Fond (1741-1819), French geologist |
|
Fayalite |
locality at Fayal Island in the Azores and Greek lithos = stone |
|
Feitknechtite |
for Walter Feitknecht (1899- ), University of Bern, who first synthesized the compound |
|
Feldspar |
Swedish feldt or fält = field and spat = spar, for the spar in the tilled fields overlying granite |
|
Fergusonite |
Robert Ferguson (1799-1865), Scottish physician |
|
Ferrierite (zeolite) |
Walter Frederick Ferrier (1865-1950), Canadian geologist and moning engineer |
|
Ferronatrite |
Latin ferrum = iron and natrium = soda describing its composition |
|
Flint |
Greek plinthos = a brick |
|
Florencite |
Willian Florence (1964-1942), Brazilian mineralogist who studied minerals in Minas Gerais |
|
Fluoborite |
from composition, a fluoborate of magnesium |
|
Fluocerite |
containing fluorine and cerium named for Ceris, an asteroid |
|
Fluorapatite |
containing fluorine and apatite |
|
Fluorite |
Latin fluere = flow, then German flüssen = fuse (German flussspat) |
|
Forsterite |
Adolarius Jacob Forster (1739-1806), English mineral collector |
|
Francolite |
Wheal (= mine) Franco, Tavistock in Devon, England, Greek lithos = stone |
|
Fuller’s earth |
clay used by the fuller to degrease cloth in a process known as fulling |
|
Furgusonite |
|
|
Gadolinite |
Johan Gadolin (1760-1852), Finnish chemist and discoverer of yttrium |
|
Galena |
Latin galena = lead ore or dross remaining after melting lead |
|
Garnet |
Latin granatum = a pomegranate since it RESEMBLes their red seeds; alternatively Latin granatus = like a grain since it RESEMBLes seeds or grains embeded in the matrix |
|
Gaylussite |
Joseph Louis Gay-Lussac (1778-1850), French chemist, Greek lithos = stone |
|
Gibbsite |
George Gibbs (1776-1833), owner of the mineral collection acquired by Yale early in the 19th century |
|
Glaserite |
??? |
|
Glauberite |
Johann Wilhelm Glauber (1603-1668), German chemist |
|
Glauconite |
Greek glaucos = originally gleaming, later bluish green, silvery, or gray |
|
Goethite |
Johann Wolfgang von Goethe (1749-1832), German poet/philosopher |
|
Graphite |
Greek for graphein = to write due to its use in making pencils |
|
Grossularite (garnet) |
Latin grossularium = gooseberry for its pale green color |
|
Groutite |
Frank Fitch Grout (1880-1958), American petrologist, U of Minnesota |
|
Guano |
Indian huanu = dung |
|
Gypsum |
from the Greek gypsos = plaster, an ancient name |
|
Hafnium |
Latin Hafnia = ancient name for Copenhagen |
|
Halite |
Greek hals = the sea (see salt) |
|
Halloysite |
Baron Omalius d’Halloy (1707-1789), Belgian geologist and first observer |
|
Hanksite |
Henry Garber Hanks (1826-1907), State Mineralogist of California |
|
Hausmannite |
Johann Friedrich Ludwig Hausmann (1782-1859), German mineralogist |
|
Hectorite |
locality at Hector, California, USA |
|
Heliodor |
Greek helios = sun — “gift of the sun”. |
|
Helvite |
Greek helvus = light yellow alluding to the mineral’s color |
|
Hematite |
Greek haimatites = bloodlike alluding to its red color |
|
Hessonite |
Greek ésson = inferior in reference to its inferior hardness and color |
|
Heulandite |
John Henry Heuland (1778-1856), English mineral collector |
|
Hiddenite |
A.E. Hidden, mine owner and first observer |
|
Hollandite |
Thomas Henry Holland (1868-1947), British geologist, Director of Geol. Survey of India |
|
Holmium |
Latin Holmia = ancient name for Stockholm |
|
Howlite |
Henry How (1828-1879), Canadian chemist and first observer |
|
Huntite |
Walter Frederick Hunt (1882-1975), American mineralogist, U of Michigan, Ann Arbor |
|
Hydroboracite |
Greek hydor = water plus boracite |
|
Illite |
locality in the state of Illinois, USA |
|
Ilmenite |
locality at the Ilmen Mountains, former USSR, where it was first located |
|
Inderborite |
Inder Lake, western Kazakhstan and composition of borate. |
|
Inderite |
Inder Lake, western Kazakhstan |
|
Inyoite |
Inyo County, California |
|
Iodine |
Greek iodes = violet alluding to its color |
|
Jacobsite |
locality at Jacobsberg, Wermland, Sweden |
|
Jade/jadeite |
Spanish term piedra de yjada = stone of the side since the stone was supposed to cure side pains |
|
Jarosite |
Jaroso Ravine in the Sierra Almagrera, Spain |
|
Jasper |
Latin iaspis, which is of oriental origin, equivalent to the Persian iashm and jashp and the Assyrian ashpu |
|
Kainite |
Greek kainos = new, recent alluding to its recent (secondary) formation |
|
Kaliborite |
composition, kalium = potassium, and boron = borate |
|
Kandite |
comprising the minerals kaolinite, nacrite, and dickite |
|
Kaolin |
Chinese Kau-ling = high ridge, a village in northwest Jiangxi Province, China, where deposits of white kaolin have long been exploited to make fine white porcelain known as china (see china clay) |
|
Kermesite |
from kermes, a name given in old chemistryto red amorphous antiminy trisulfide often mixed with antimony trioxide |
|
Kernite |
locality at Kern County, California |
|
Kieselguhr |
German kiesel = flint and guhr = earthy sediment deposited in water |
|
Kieserite |
Dietrich Georg Kieser (1779-1862), President of Jena Acadamy, Germany |
|
Kornerupine |
Andreas Nikolaus Kornerup (1857-1881), Danish geologist |
|
Kotoite |
Bundjirom Koto (1856-1935), Japanese geologist and petrographer, U of Tokyo |
|
Kramerite |
locality at Kramer boron deposit, California. A.k.a. probertite. |
|
Kurnakovite |
Nikolai Semenovich Kurnakov (1860-1941), Russian mineralogist |
|
Kunzite |
G.F. Kunz, American mineralogist |
|
Kyanite |
Greek kyanos = dark blue reflecting its color |
|
Labradorite |
the mineral was first brought from the Isle of Paul, Labrador, about 1770 |
|
Langbeinite |
A. Langbein, German chemist of Leopoldshall |
|
Lanthanum |
Greek lanthanein = to be unseen, unnoticed, or concealed |
|
Lapis lazuli |
Latin lapis = a stone and Persian lazhward = blue color |
|
Laumontite (zeolite) |
François Pierre Nicolas Giller de Laumont (1747-1834), French discoverer |
|
Lautarite |
locality at Oficina Lautaro, Antofagasta Province, Chile |
|
Lecontite |
John Lawrence LeConte (1825-1883), American entomologist of Philadelphia who discovered the mineral |
|
Leonite |
Leo Strippelmann, director of the salt work at Westerregeln, Germany |
|
Lepidocrocite |
Greek lepis = scale in reference to the scaly or feathery habit, and (Latin) crocinus = saffron, golden, yellow for its color |
|
Lepidolite |
Greek lepis = scale and lithos = stone because of its micaceous structure |
|
Leucite |
Greek leukos = white reflecting its whire or gray color |
|
Leucoxene |
Greek leukos = white and xenos = stranger alluding to its color and secondary nature |
|
Lime |
Old English; related to Dutch iljm & Latin limus = mud, linere = to smear |
|
Limonite |
Greek leimon = meadow since it often occurs in bogs and swamps |
|
Lithiophilite |
Greek lithos = stone and philos = loving alluding to its composition |
|
Lithiophorite |
Greek lithos = stone and to bear in reference to its lithium content |
|
Lithium |
Greek lithos = stone |
|
Loeweite |
Alexander Loewe (1808-1846), German chemist |
|
Loparite |
Russian name for the Lapp inhabitants of the Kola Peninsula |
|
Ludwigite |
Ernst Ludwig (1842-1915), Austrian chemist, U of Vienna |
|
Lutetium |
Lutetia, the ancient name for Paris |
|
Maghemite |
from the fisrt syllables of magmetite and hematite referring to the magnetism and and composition |
|
Magnesite |
see magnesium; applied to a series of magnesium salts by J.C. Delanethrie in 1795; D.L.G. Karsten first restricted it to the natural carbonate in 1808 |
|
Magnesium/ magnesia |
Possibly Latin magnesia, a mineral said to be brought from the province of Magnesia in Thessaly, Greece > magnesia alba > “magnesia” and “magnesium” (magnesia negra > “manganese”); See manganese. |
|
Magnetite |
Middle Latin magnes = magnet in reference to its magnetic properties; or from Magnes, a shepherd who first discovered the mineral on Mount Ida when the rock was attracted to the nails in his shoes |
|
Manganese |
Possibly Latin magnesia, a mineral said to be brought from the province of Magnesia in Thessaly, Greece > magnesia negra and corrupted to “manganese” (in common with magnesia alba > “magnesia” and “magnesium”; alternatively Greek mangania = magic. See magnesium/magnesia. |
|
Manganite |
manganese content (see above) |
|
Marble |
Greek marmairein = to shine, marmaros = white glistening stone |
|
Marcasite |
probably Arabic or Moorish for pyrite and similar substances |
|
Mayenite |
locality near Mayen, Eifel district Rhineland-Palatinate, Germany |
|
Meerschaum |
Greek meer = sea and schaum = froth for its light weight and color |
|
Mendozite |
Mendoza, Argentina |
|
Meyerhofferite |
Wilhelm Meyerhoffer (1864-1906), German chemist |
|
Mica |
Latin micare = to shine or to glitter or the Latin mica = a crumb or grain |
|
Microcline |
Greek mikro = little and klinein = to incline in reference to its characteristic variation of cleavage angle from 90o |
|
Millisite |
F.T. Mills, of Lehi, Utah, the first observer |
|
Mirabilite |
Latin sal mirabilis = wonderful salt, Greek lithos = stone |
|
Mohavite |
Mohave desert, California. A.k.a. tincalconite. |
|
Monazite |
Greek monazein = to be alone alluding to its rarity |
|
Montebrasite |
locality at Mintebras, Creuse, France |
|
Montmorillonite |
locality at Montmorillon, Vienne, France |
|
Mordenite (zeolite) |
Morden, King’s County, Nova Scotia, Canada |
|
Morganite |
John Pierpont Morgan, American banker and gem enthusiast |
|
Mullite |
locality at the island of Mull, Scotland, Greek lithos = stone |
|
Muscovite |
Muscovy glass, when first described from Muscovy Province, Russia |
|
Nahcolite |
acronym of Na, H, C, O plus Greek lithos = stone |
|
Natrolite (zeolite) |
Latin natrium or Greek natron = native soda plus lithos = stone |
|
Natron |
Latin natrium or Greek nitron = native soda |
|
Neodymium |
Greek neos = new and didymos = twin |
|
Nepheline |
Greek nephele = cloud alluding to the cloudy appearance developed on immersing nepheline in strong acid |
|
Nephrite |
Latin lapis nephriticus = kidney stone since it was often worn to remedy diseases of the kidnies |
|
Nesquehonite |
Nesquehoning near Lansford, Carbon County, Pennsylvania |
|
Niter/Nitrates |
ancient origin: Latin nitrum, the Greek for nitron, the Hebrew nether; perhaps originally from Nitria, a city in Upper Egypt |
|
Nontronite |
locality at Arrondissement of Nontron, near the village of Saint Pardoux, France |
|
Northupite |
Charles H. Northup (b. 1861), American grocer and first observer |
|
Novaculite |
Latin novacula = razor hone alluding to its use as a sharpening stone |
|
Nsutite |
locality at the Nsuta Mine, Ghana |
|
Ochre |
Latin and Greek ochra = pale or pale yellow alluding to its color |
|
Offertite (zeolite) |
Albert Jules Joseph Offret (1857-?), professor, Lyons, France |
|
Olivine |
Latin oliva = olive alluding to its olive green color |
|
Onyx |
Greek onyx = claw, fingernail, hoof in reference to the color |
|
Opal |
from Sanskrit upala = stone or precious stone |
|
Orthoclase |
Greek for straight and klasis = fracture in reference to its cleavage angle of 90° |
|
Palygorskite |
locality at “in der Paligorischen Distanz” of the second mine on the Popovka River, Urals, former USSR, where it was observed |
|
Pandermite |
locality at Panderma, the old name for Bandirma, a port in Turkey |
|
Parisite |
J.J. Paris, proprietor of the mine at Muzo, north of Bogata, Colombia, where the mineral was discovered |
|
Peat |
Anglo-Latin peta = piece of turf |
|
Pentlandite |
Joseph Barclay Pentland (1797-1873), Irish natural scientist and traveler |
|
Periclase |
Greek peri = around and klasis = fracture due to its perfect cubic cleavage |
|
Peridot |
French péridot of unknown origin |
|
Perlite |
French perle = pearl due to its pearly luster and form when hammered |
|
Perovskite |
|
|
Petalite |
Greek petalon = leaf and lithos = stone alluding to its leaflike cleavage |
|
Phenak(c)ite |
Greek phenax = to cheat since it was often mistaken for quartz |
|
Phengite |
Greek and Latin phengites = shine in reference to its luster |
|
Phillipsite (zeolite) |
William Phillips (1775-1829), British mineralogist, founder of the Geological Society of London |
|
Phlogopite |
Greek phlogistos = to burn or inflame alluding to its reddish tinge |
|
Phonolite |
Greek phone = sound and lithos = stone in reference to its ring when struck with a hammer |
|
Phosphate |
Greek for phos = light and phoros = bearer due to its spontaneous combustion; frpm the Latin meaning morning star |
|
Pinnoite |
Mt. Pinno, Chief Councellor of Mines, of Halle, Germany |
|
Pirssonite |
Louis Valentine Pirsson (1860-1919), American mineralogist at Yale |
|
Plagioclase |
Greek plagios = oblique and klasis = fracture in reference to the oblique angles between its best cleavages |
|
Plumbago |
Latin plumbum = lead since graphite was misidentified as galena |
|
Pinite |
|
|
Polianite |
N.A. |
|
Pollucite |
Pollux, the twin brother of Castor in Classical mythology, in reference to its association with the mineral castor (old name for petalite) |
|
Polyhalite |
Greek polys = much or many and hals = salt due to the component salts |
|
Portland cement |
resembles a building stone on the Isle of Portland, Dorset, England |
|
Portlandite |
from Portland cement, locality at the Isle of Portland, Dorset, England, with which the synthetic compound was known to be associated |
|
Potash |
from pot and ash, originally prepared by evaporating the lixivium of wood ashes in iron pots (see soda ash) |
|
Pozzalana |
locality at Pozzuoli near Mount Vesuvius where a tuff was extracted by the Romans |
|
Praeseodymium |
Greek prasios = green and didymos = twin |
|
Priceite |
Thomas Price (b. 1837?), Welsh-American mineralogist. A.k.a Pandemite. |
|
Probertite |
Frank Holman Probert (1876-1940), Dean of the Mining College, U of Cal. A.k.a. kramerite. |
|
Promethium |
Prometheus, a Titan in Greek mythology, who made a man of clay from fire stolen from heaven |
|
Psilomene |
Greek psilos = naked, bare and melas = black alluding to its appearance |
|
Pumice |
Latin pumex = pumice or porous stone from spuma = foam |
|
Pyrrhotite |
Greek for redness aluding to the liveliness of its color |
|
Pyrite |
Greek pyrites = flint or millstone from pyros = a fire since it gives off sparks when struck |
|
Pyrochlore |
Greek pyros = a fire and chloros = green since it turns green on ignition |
|
Pyrolusite |
Greek pyros = a fire and lusite = to wash due to its use to decolorize glass |
|
Pyrope (garnet) |
Greek pyr = fire and ops = eye alluding to its fire-red color |
|
Pyrophyllite |
Greek for pyro = a fire, phyllo = a leaf, and lithos = stone referring to the effect of heat separating the laminae in foliated varieties |
|
Quartz |
Saxon word querkluftertz = cross-vein ore; first condensed to querertz; or West Slavic word kwardy |
|
Ramsdellite |
Lewis Stephen Ramsdell (1895-1975), American mineralogist, U of Michigan, Ann Arbor |
|
Rare earths |
named by Johann Gadolin as a literal description of a group of elements |
|
Rhodochrosite |
Greek rhodochros = rose colored alluding to its color |
|
Rhodonite |
Greek rhodon = a rose alluding to its color |
|
Roseki |
Japanese for waxy stone referring to its wax-like appearance. |
|
Roscoelite |
Henry Enfield Roscoe (1833-1915), a chemist from Manchester, England, who first to prepared pure vanadium |
|
Ruby |
Latin rubeus = red alluding to its color |
|
Rutile |
French shining from Latin rutilus = red alluding to its color |
|
Sanbornite |
for Frank Sanborn, American mineralogist. Div. Mines, Dept. Natural Resources, CA |
|
Sanidine |
Greek sanis (-idos) = a board, a table in reference to the mineral’s tabular habit |
|
Salt |
Latin sal which originated from the Greek for hals = the sea (see halite) |
|
Samarskite |
Vasilii Erafovich Samarski-Bykhovets (1803-1870), of the Russian Corps of Mining Engineers |
|
Saponite |
Latin sapo (-idos) = soap for its soaplike appearance |
|
Sapphire |
ancient name of uncertain origin; possibly Hebraic sappir and Sanskrit sanipruja; applied by the ancients to lazurite |
|
Sassolite |
Sasso, Tuscany, Italy where first observed, Greek lithos = stone |
|
Searlesite |
John W. Searles, Californian pioneer; Searles Lake, CA, named for him |
|
Selenite |
Greek selenites (lithos) = moon (stone) since it was supposed to wax and wane with the moon and/or it has moon-like white reflections |
|
Sellaite |
Quntino Sella (1827-1884), Italian mining engineer and mineralogist |
|
Senarmonite |
Henri Hureau de Sénarmont (1808-1862), French physicist and mineralogist, School of Mines, Paris, who first described the species |
|
Sepiolite |
Greek sepion = the bone of the cuttle-fish and lithos = stone since the bone of the cuttle-fish is light and porous like the mineral |
|
Sericite |
Greek for silky alluding to its silky luster |
|
Serpentine |
Latin serpens = snake because of the similar surface patterns |
|
Shortite |
Maxwell Naylor Short (1889-1952), American mineralogist, U of Arizona, and Greek lithos = stone |
|
Siderite |
Greek sideros = iron in reference to its composition |
|
Sienna |
locality at the town of Sienna in Tuscany, northern Italy |
|
Silica |
Latin silex = flint |
|
Sillimanite |
Professor Benjamin Silliman (1779-1864), American mineralogist, Yale |
|
Slate |
|
|
Smectite |
Greek smektis = fuller’s earth from smechein = to wipe off, to cleanse because of its property of extracting grease from cloth (see Fuller’s Earth) |
|
Soda |
possibly from the name of a mineral that occurs near Djebel es Soda, Libya. Alternatively, the Spanish soda (from the Arabian suvvad = a plant from the ash of which soda was obtained in Sicily and Spain), or from the medieval Latin sodanum = a remedy for headaches (from the Arabic suda = headache). |
|
Soda ash |
from soda and ash, originally prepared by evaporating the lixivium of wood ashes in iron pots (see potash) |
|
Sodalite |
from composition, Latin solidus = solid since it was a solid used in glassmaking (see soda ash) |
|
Sodium sulfate |
chemical name |
|
Spessartine (garnet) |
locality at Spessart in northwestern Bavaria, Germany |
|
Sphalerite |
Greek for trecherous or slippery since it was often mistaken for galena but yielded no lead |
|
Sphene |
Greek for wedge due to characteristic habit of the crystals |
|
Spinel |
Latin spinella = little thorn referring to its spine-shaped octahedral crystals |
|
Spodumene |
Greek spodoun = to reduce to ashes refers either to its ash-gray color or the ash-colored mass formed when heated before the blowpipe |
|
Stassfurtite |
locality at Stassfurt, Germany, where it is associated with potash. A.k.a. boracite |
|
Staurolite |
Greek stauros = a cross and lithos = stone because of its common cruciform twins |
|
Steatite |
Greek steatos = suet |
|
Stibiconite |
Greek stimmi and Latin stibium = antimony and Greek for powder or dust, because it often occurs as a powder |
|
Stibnite |
Greek stimmi and Latin stibium = old names for antimony |
|
Strontianite |
locality at Strontian, a small town in Argyllshire, Scotland |
|
Suanite |
locality at Suan County, Korea |
|
Sulfur |
Latin sulfur, an old name; akin to Sanskrit sulvere |
|
Sulphohalite |
from composition, a sulfate with the halogen elements Cl and F |
|
Suzorite |
locality at Suzor Township near Boucherville, Quebec, Canada (phlogopite mica) |
|
Sylvite |
old chemical name Sal digestivus Sylvii or digestive salt of Francois Sylvius de la Boë (1614-1672), Dutch chemist and physician of Leyden |
|
Syngenite |
Greek syn = with, together with, or related to in reference to its similarity to polyhalite |
|
Szaibelyite |
Stephan Szaibely (1777-1855), Hungarian mine surveyor of Rézbánya. A.k.a. ascherite |
|
Talc |
Arabic talq |
|
Tamarugite |
locality at Tamarugal, Pampa, Chile |
|
Tanzanite |
locality at Tanzania, Africa |
|
Tephroiite |
Greek for ash-colored due to its color |
|
Teruggite |
Mario E. Teruggi, geologist, Universitatd Nacional La Plata, Argentina |
|
Thenardite |
Louis Jacques Thénard (1777-1857), French chemist, U of Paris |
|
Thermonatrite |
Greek therme = heat and natron = soda since it forms from drying soda |
|
Thorium |
Thor, Scandinavian god of thunder and lightening in reference to its use in energy |
|
Thulite |
Thule, the ancient name of Scandinavia |
|
Tincal |
Sanskrit tincal or Malay tingkal = borax. A.k.a. borax. |
|
Tincalconite |
Sanskrit tincal = borax and Greek konis = dust or powder; the fact it can form from the dehydration of borax A.k.a. mohavite. |
|
Titanium/ |
Latin Titani and Greek Titanes = a Titan, in Greek mythology any one of twelve children of Uranus ( Heaven) and Gaea (Earth); denotes strength |
|
Todorokite |
locality at the Todoroki mine, Hokkaido, Japan |
|
Topaz |
from the Greek Topazion, an island in the Red Sea, meaning to seek since the island was often covered in mist |
|
Toseki |
Japanese meaning “stones used for pocelain raw material (pottery stone) |
|
Tourmaline |
Singhalese turamali = originally applied to zircon and other gems by jewelers in Sri Lanka |
|
Tremolite |
locality at Tremola Valley, near St. Gotthard, Switzerland, and Greek lithos = stone |
|
Tridymite |
Greek tridymos = threefold since the crystals are often trillings |
|
Tripoli |
locality at Tripoli, Libya, in North Africa |
|
Trona |
Arabic name of the native salt |
|
Tsavolite |
locality at Tsavo National Park, Kenya , first discovered, and Greek lithos = stone |
|
Tunellite |
George Tunell (1900- ), American geochemist, U of California, Los Angeles |
|
Turquoise |
Old French turqueise = Turkish as stones came to Europe from Persia via Turkey |
|
Tychite |
in Greek mythology Tyche = the Goddess of Chance alluding to the fact that two tychite crystals in a stock of 5,000 northupite crystals were the first and the last to be found |
|
Tysonite |
S.T. Tyson who collected and supplied the specimens in the original study |
|
Ulexite |
George Ludwig Ulex (1811-1883), German chemist and first observer |
|
Umber |
locality at the Umbria idistrict of Italy or possibly Latin umbra = a shade or shadow |
|
Uralborite |
locality at Ural Mountains in the former USSR and its borate content |
|
Uvarovite (garnet) |
Count Sergei Semeonovich Uvarov (1786-1855), Russian nobleman, Imperial Academy of St. Petersburg |
|
Valentinite |
Basilius Valentinus (pseudonym for Johannes Thölde), German alchemist working on the properties of antimony in the late 17th and early 18th century. |
|
Vanthoffite |
Jacobus Hendricus van ‘tHoff (1852-1911), Dutch physical chemist |
|
Veatchite |
Dr. John A. Veatch who first discovered boracic acid in northern Californian springs |
|
Vermiculite |
Latin vermiculare = to breed worms alluding to its appearance after exfoliation and Greek lithos = stone |
|
Vernadite |
Vladimir Ivanovich Vernadskii (1863-1945), Russian naturalist and geochemist |
|
Vesuvianite |
locality at Mt. Vesuvius, Italy, where it was found in ejected blocks |
|
Villiaumite |
French explorer Villiaume who brought the specimen from Guinea |
|
Vonsenite |
Magnus Vonsen (1879-1954), American mineral collector of Petaluma, CA, who was interested in borate minerals. A.k.a. paigeite. |
|
Wad |
provincial English word for black, soft powders of unknown origin |
|
Wairakite |
locality at Wairakei in the central part of the North Island, New Zealand |
|
Wardite |
Henry Augustus Ward (1834-1906), American naturalist, Rochester, NY |
|
Wavellite |
William Wavell (d.1829), English physician, Horwood Parish, Devon, UK, and Greek lithos = stone |
|
Wegscheiderite |
Rudolph Wegscheider, chemist who formed the compound synthetically |
|
Witherite |
William Withering (1741-1799), English physician, botanist & mineralogist |
|
Wollastonite |
William Hyde Wollaston (1766-1828), English chemist and mineralogist |
|
Xenotime |
Greek xenos = foreign, a stranger and time = to honor alluding to the fact that crystals are small and rare, and were long unnoticed; originally mispelled kenotime, Greek for vain and to honor |
|
Ytterbium/yttrium |
locality at Ytterby, Sweden |
|
Zeolites |
Greek zein = to boil and lithos = stone (i.e. boiling stones) |
|
Zinnwaldite |
locality at Zinnwald, Bohemia, itself named for the local tin (German Zinn) veins |
|
Zircon |
from Arabic zarqun, derived from the Persian zar = gold and gun = color |
|
Zoisite |
Siegmund Zois, Baron von Edelstein (1747-1819), Austrian scholar |
Sources: Fleischer, M, 1975, Glossary of Mineral Species; Lyman, K., ed., 1984, Simon & Schuster’s Guide to Gems and Precious Stones; Mitchell, R.S., 1979, Mineral Names What Do They Mean?; Spencer, L.J., M.H. Hay, et al, various dates, “Annual lists of new mineral names”, Mineralogical Magazine; Chambers Etymological English Dictionary; Encyclopaedia Britannica; Webster’s New Twentieth Century Dictionary (unabridged). |
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MINERAL NAMES
•Januari 20, 2009 • Tinggalkan sebuah KomentarMining as a Basic Industry
•Januari 20, 2009 • Tinggalkan sebuah KomentarMining and Agriculture are 2 basic industries which led to the development of modern civilization.
Other basic industries include farming and fishing and more recently manufacturing.
Agriculture gives us chiefly our food and the materials from which clothes and some of our buildings are made.
Mining supplies us with :
structural material, such as stone, glass sand, clays and cement fuels, natural gas, coal and petroleum abrasives, such as garnet and corundum fertilizers, potash, phosphates and nitrates various industrial uses, such as sulfur, graphite, borax, and asbestos metallic minerals, gold, silver, copper, lead, zinc, iron and aluminum precious stones, diamonds, rubies and sapphires fissionable materials
rare metals.
From these substances come the materials which are of such vital importance in time of war and which, in times of peace, are so necessary for the growth of our arts, sciences and industry.
National Importance
The importance of minerals to national security was firmly established during World War I. When the free world entered into the conflict in 1917, the most serious question that arose in conducting war was the shortage of ships for supplying food and fuel and especially the minerals needed for manufacture of explosives and other products necessary for the prosecution of war.
Along with war minerals, fuels and iron held positions of greatest importance. Fortunately, the allies had large reserves of these fuels, especially coal, which is of greater commercial value than iron and steel. So valuable was coal, that laws were established for the purpose of controlling the transportation and distribution of coal throughout the free world. Oil was also conserved by eliminating unnecessary hauls and waste.
Mineral Resources and International Relations
The importance of international negotiations to a country whose reserves of necessary minerals has been depleted is obvious. Mines are WASTING ASSETS and a country once rich in minerals may later be compelled to import these essential materials. For any nation, a well balanced supply of minerals is better than a supply of some and a lack of others. Of these resources, the mineral fuels and iron are of primary importance. Copper, lead, and zinc come next. With them should be ranked the fertilizer group of phosphates, potash and nitrates together with sulfur, of so much importance in the chemical industries. Gold and silver are of little importance in building up industrial development.
Nickel, manganese, fluorspar, vanadium, tungsten and other mineral products – asbestos, mica, mercury, graphite, antimony and tin – are needed in industry. However, the quantities required are small and can be transported long distances to industrial centers. Industrial nations must have secure access to such resources and their control is a matter of international concern.
Most industrial nations lack sufficient resources to be self-sufficient and normally STOCKPILE the necessary mineral raw resources. Under the urge of economic nationalism, there has been a multiplication of production in the mineral industry throughout the world, not because of a shortage of world supply but through fear of being at the mercy of another nation in times of emergency.
Mining Communities
Well over 100 communities across Canada with a total population of over 600 000 are dependent on the minerals industry. These communities are located in all regions of the country, but mainly in remote and rural areas. The population of these dependent communities ranges in size from a few hundred people (for example, Ming’s Bight, Newfoundland, and Nanisivik, Nunavut) to much larger communities with populations in the tens of thousands (for example, Rouyn-Noranda, Quebec, and Timmins, Ontario).
In other Canadian communities, such as Sudbury, the minerals industry is an integral part of their diversified economy. And a number of communities depend on a combination of natural resource industries — energy, forestry and minerals. For example, Hinton,Alberta, has ties to the mining, forestry and energy sectors. The urban centres of Toronto, Montreal and Vancouver are home to many of the financial services used by the minerals industry, including those provided by stock exchanges, underwriters and brokerage houses. In addition many mining companies have their headquarters in these urban centres.
Over 2200 Canadian-based companies sell specialized scientific or technical products for use by mining companies operating in Canada. Suppliers of mining goods and services are located in more than 400 communities across Canada. Firms in Toronto,Vancouver and Sudbury account for 45% of goods supplied to mining companies. Mining companies tend to purchase a significant portion (over one third) of their goods and materials from suppliers within an 80-km radius of their operations. The minerals industry holds the promise of economic development opportunities for the Aboriginal population, as approximately 1200 Aboriginal communities are located within 200 km of mineral ands metals activities.
The Canadian non-fuel minerals industry continues to make an important contribution to Canada’s economy: it contributes almost 4% of the national GDP. The minerals industry provides some of the highest weekly earnings in the economy — averaging over $1000: this far surpasses the average weekly earnings across the Canadian economy, which are about $600. Employment in the minerals industry remains a source of strength in the Canadian economy.
In 2000, approximately 53 000 Canadians were directly employed in the mining industry and about another 350 000 were employed in the downstream minerals industry. Canada Resources naturelles Canada Natural Resources Canada The Importance of Mining to Canadian Communities Many communities in Canada have an important stake in the future of this nation’s minerals industry. Natural Resources Canada recognizes the importance of the minerals industry to Canadian communities.
FLY ASH
•Januari 20, 2009 • Tinggalkan sebuah KomentarFly ash is the finely divided mineral residue resulting from the combustion of ground or powdered coal in electric generating plant (ASTM C 618). Fly ash consists of inorganic matter present in the coal that has been fused during coal combustion. This material is solidified while suspended in the exhaust gases and is collected from the exhaust gases by electrostatic precipitators. Since the particles solidify while suspended in the exhaust gases, fly ash particles are generally spherical in shape (Ferguson et. al., 1999). Fly ash particles those are collected in electrostatic precipitators are usually silt size (0.074 – 0.005 mm).
Fly Ash Classification
Fly ash is a pozzolanic material and has been classified into two classes, F and C, based on the chemical composition of the fly ash. According to ASTM C 618, the chemical requirements to classify any fly ash are shown in Table 3.1.
Table 3.1. Chemical Requirements for Fly Ash Classification
|
Properties |
Fly Ash Class |
|||||||
|
|
Class F |
Class C |
||||||
| Silicon dioxide (SiO2) plus aluminum oxide (Al2O3) plus iron oxide (Fe2O3), min, % |
70.0 |
50.0 |
||||||
| Sulfur trioxide (SO3), max, % |
5.0 |
5.0 |
||||||
Moisture Content, max, % |
3.0 |
3.0 |
||||||
| Loss on ignition, max, % |
6.0* |
6.0 |
||||||
| * The use of class F fly ash containing up to 12% loss of ignition may be approved by the user if acceptable performance results are available | ||||||||
Class F fly ash is produced from burning anthracite and bituminous coals. This fly ash has siliceous or siliceous and aluminous material, which itself possesses little or no cementitious value but will, in finely divided form and in the presence of moisture, chemically react with calcium hydroxide at ordinary temperature to form cementitious compounds (Chu et. al., 1993). Class C fly ash is produced normally from lignite and sub-bituminous coals and usually contains significant amount of Calcium Hydroxide (CaO) or lime (Cockrell et. al., 1970). This class of fly ash, in addition to having pozzolanic properties, also has some cementitious properties (ASTM C 618-99).
Color is one of the important physical properties of fly ash in terms of estimating the lime content qualitatively. It is suggested that lighter color indicate the presence of high calcium oxide and darker colors suggest high organic content (Cockrell et. al., 1970).
Fly Ash Chemistry
Chemical constituents of fly ash mainly depend on the chemical composition of the coal. However, fly ash that are produced from the same source and which have very similar chemical composition, can have significantly different ash mineralogies depending on the coal combustion technology used. Because of this, the ash hydration properties as well as the leaching characteristic can vary significantly between generating facilities.
The amount of crystalline material versus glassy phase material depends largely on the combustion and glassification process used at a particular power plant. When the maximum temperature of the combustion process is above approximately 12000 C and the cooling time is short, the ash produced is mostly glassy phase material (McCarthy et. al., 1987). Where boiler design or operation allows a more gradual cooling of the ash particles, crystalline phase calcium compounds are formed.
The relative proportion of the spherical glassy phase and crystalline materials, the size distribution of the ash, the chemical nature of glass phase, the type of crystalline material, and the nature and the percentage of unburned carbon are the factors that can affect the hydration and leaching properties of fly ash (Roy et. al., 1985). The primary factors that influence the mineralogy of a coal fly ash are (Baker, 1987):
1. Chemical composition of the coal
2. Coal combustion process including coal pulvarization, combustion, flue gas clean up, and fly ash collection operations
3. Additives used, including oil additives for flame stabilization and corrosion control additives.
The minerals present in the coal dictates the elemental composition of the fly ash. But the mineralogy and crystallinity of the ash is dictated by the boiler design and operation.
Hydration of Fly Ash
Formation of cementitious material by the reaction of free lime (CaO) with the pozzolans (AlO3, SiO2, Fe2O3) in the presence of water is known as hydration. The hydrated calcium silicate gel or calcium aluminate gel (cementitious material) can bind inert material together. For class C fly ash, the calcium oxide (lime) of the fly ash can react with the siliceous and aluminous materials (pozzolans) of the fly ash itself. Since the lime content of class F fly ash is relatively low, addition of lime is necessary for hydration reaction with the pozzolans of the fly ash. For lime stabilization of soils, pozzolanic reactions depend on the siliceous and aluminous materials provided by the soil. The pozzolanic reactions are as follows:
Ca(OH)2 => Ca++ + 2[OH]-
Ca++ + 2[OH]- + SiO2 => CSH
(silica) (gel)
Ca++ + 2[OH]- + Al2O3 => CAH
(alumina) (gel)
Hydration of tricalcium aluminate in the ash provides one of the primary cementitious products in many ashes. The rapid rate at which hydration of the tricalcium aluminate occurs results in the rapid set of these materials, and is the reason why delays in compaction result in lower strengths of the stabilized materials.
The hydration chemistry of fly ash is very complex in nature. So the stabilization application must be based on the physical properties of the ash treated stabilized soil and cannot be predicted based on the chemical composition of the fly ash.
Leaching from Fly Ash
The total metals content for a specific ash source depends on the composition of the coal. The potential for leaching of these metals not only depends on the total metals content but also influenced by the crystallinity of the fly ash, as this would dictate whether the metals are incorporated within the glasseous phase or within crystalline compounds, which will hydrate (ACAA). The metals in the glasseous phase are expected to leach at much lower rate than that from the crystalline phase.
Since the degree of crystallinity is a function of boiler design and remains relatively constant for a given source, leachable materials remain relatively constant for a given ash source. A number of state regulatory agencies have issued source approval for specific generating facilities after the consistency of these materials had been demonstrated.
For stabilized soil, the leachability of metals not only depends on the property of the fly ash but also the soil that are used for stabilized soil. Some part of these metals leached from the fly ash will be adsorbed on the clay minerals of the soil.
What is Silica?
•Januari 20, 2009 • Tinggalkan sebuah KomentarSilica is the name given to a group of minerals composed of silicon and oxygen, the two most abundant elements in the earth’s crust. Silica is found commonly in the crystalline state and rarely in an amorphous state. It is composed of one atom of silicon and two atoms of oxygen resulting in the chemical formula SiO2.
The first industrial uses of crystalline silica were probably related to metallurgical and glass making activities in three to five thousand years BC. It has continued to support human progress throughout history, being a key raw material in the industrial development of the world especially in the glass, foundry and ceramics industries. Silica contributes to today’s information technology revolution being used in the plastics of computer mouses and providing the raw material for silicon chips.
Geology and occurrence of industrial silica
Silica exists in nine different crystalline forms or polymorphs with the three main forms being quartz, which is by far the most common, tridymite and cristobalite. It also occurs in a number of cryptocrystalline forms. Fibrous forms have the general name chalcedony and include semi-precious stone versions such as agate, onyx and carnelian. Granular varieties include jasper and flint. There are also anhydrous forms – diatomite and opal.
Quartz is the second most common mineral in the earth’s crust. It is found in all three of the earths rock types – igneous, metamorphic and sedimentary. It is particularly prevalent in sedimentary rocks since it is extremely resistant to physical and chemical breakdown by the weathering process. Since it is so abundant, quartz is present in nearly all mining operations. It is present in the host rock, in the ore being mined, as well as in the soil and surface materials above the bedrock, which are called the overburden.
Most of the products sold for industrial use are termed silica sand. The word “sand” denotes a material whose grain size distribution falls within the range 0.06-2.00 millimetres. The silica in the sand will normally be in the crystalline form of quartz. For industrial use, pure deposits of silica capable of yielding products of at least 95% SiO2 are required. Often much higher purity values are needed. Silica sand may be produced from sandstones, quartzite and loosely cemented or unconsolidated sand deposits. High grade silica is normally found in unconsolidated deposits below thin layers of overburden. It is also found as “veins” of quartz within other rocks and these veins can be many metres thick. On occasions, extremely high purity quartz in lump form is required and this is produced from quartzite rock. Silica is usually exploited by quarrying and it is rare for it to be extracted by underground mining.
Physical and chemical properties
The three major forms of crystalline silica -quartz, tridymite and cristobalite- are stable at different temperatures and have subdivisions. For instance, geologists distinguish between alpha and beta quartz. When low temperature alpha quartz is heated at atmospheric pressure it changes to beta quartz at 573oC. At 870oC tridymite is formed and cristobalite is formed at 1470oC. The melting point of silica is 1610oC, which is higher than iron, copper and aluminium, and is one reason why it is used to produce moulds and cores for the production of metal castings.
The crystalline structure of quartz is based on four oxygen atoms linked together to form a three-dimensional shape called a tetrahedron with one silicon atom at its centre. Myriads of these tetrahedrons are joined together by sharing one another’s corner oxygen atoms to form a quartz crystal.
Quartz is usually colourless or white but is frequently coloured by impurities, such as iron, and may then be any colour. Quartz may be transparent to translucent, hence its use in glassmaking, and have a vitreous lustre.
Quartz is a hard mineral owing to the strength of the bonds between the atoms and it will scratch glass. It is also relatively inert and does not react with dilute acid. These are prized qualities in various industrial uses.
Depending on how the silica deposit was formed, quartz grains may be sharp and angular, sub-angular, sub-rounded or rounded. Foundry and filtration applications require sub-rounded or rounded grains for best performance.
Processing technologies
Silica deposits are normally exploited by quarrying and the material extracted may undergo considerable processing before sale. The objectives of processing are to clean the quartz grains and increase the percentage of silica present, to produce the optimum size distribution of product depending upon end use and to reduce the amount of impurities, especially iron and chromium, which colour glass.
Cleaning the quartz grains and increasing silica content is achieved by washing to remove clay minerals and scrubbing by attrition between particles. Production of the optimum size distribution is achieved by screening to remove unwanted coarse particles and classification in an upward current of water to remove unwanted fine material. Quartz grains are often iron stained and the staining may be removed or reduced by chemical reaction involving sulphuric acid at different temperatures. Impurities present as separate mineral particles may be removed by various processes including gravity separation, froth flotation and magnetic separation. For the highest purity, for electronics applications, extra cleaning with aggressive acids such as hydrofluoric acid combined with thermal shock may be necessary.
After processing, the sand may be dried and some applications require it to be ground in ball mills to produce a very fine material, called silica flour. Also, quartz may be converted to cristobalite in a rotary kiln at high temperature, with the assistance of a catalyst. Some specialist applications require the quartz to be melted in electric arc furnaces followed by cooling and grinding to produce fused silica.
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Industrial Silica Applications |
Silica has played a continuous part in man’s development and been one of the basic raw materials supporting the industrial revolution (as refractory, flux, and moulding sand) and today’s information technology revolution (providing the raw material for silicon chips).
Industrial silica is used in a vast array of industries, the main ones being the glass, foundries, construction, ceramics, and the chemical industry.
Silica in its finest form is also used as functional filler for paints, plastics, rubber, and silica sand is used in water filtration and agriculture.
Other examples of everyday uses include the construction and maintenance of an extensive range of sports and leisure facilities.
Crystalline silica is also irreplaceable in a series of high-tech applications, for example in optical data transmission fibres and precision casting. It is also used in the metallurgical industry as the raw material for silicon metal and ferrosilicon production. Another specialized application is in the oil production.
Altogether there are several hundreds of applications of industrial silica in our daily life. Silica products have become so obvious to us that we don’t even know they are being applied. Reading this page, you will be surprised to find out how many times per day you see, touch and use products containing crystalline silica.
For more information on the socio-economic aspects related to industrial silica uses, please have a look into the Socio – Economic Review of Crystalline Silica Usage, Brian Coope, September 1997, whose conclusion is that if man wishes to live in silica free environment he must move to another planet.
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Glass Industry |
Silica is the main ingredient of this vital material. The glass products containing silica include containers (bottles, jars, drinking vessels), flat glass (for windows, automotive glass, mirrors, etc.), decorative glass (glasses, decanters, bowls, figurines), fibreglass (reinforcing and insulating), technical glass (screens), and optical glass (spectacles and binoculars).
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Foundries |
Quartz sand is a basic material for the production of moulds and cores in metal casting. It is also used for precision casting, dental applications and jewellery casting.
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Building and construction |
The construction industry is by far the largest volume consumer of silica minerals. Industrial silica is used in construction aggregates, in concrete, dimension stone, masonry mortars, tile glues, floor screeds, cement manufacture, road line markings, asphalt, in bridge and sewer refurbishment, in decorative bricks, not to mention in glass and steel structures.
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Ceramics |
Industrial silica is a structural ingredient of clay bodies and a major constitutent of ceramic glazes, ranging from refractory bricks to wall bricks, and from sanitaryware to tableware and tiles.
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Chemical industry |
Quartz derivatives are used in many areas, such as pesticides, fertilisers and pharmaceuticals preparations. Another derivative from industrial silica is silicon carbide, which is the raw materials for abrasives, anti-slip and polishing products.
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Functional fillers |
for paints, plastics, rubber, sealants
Silica in its finest forms find important usage as reinforcing filler for use in paint, plastics, rubber, and sealants.
In paints, silica is used to render the paint more resistant to chemicals and for enhancing hardness and wear resistance.
Ultrafine silica displays strong reinforcing properties in rubber formulations and is thus a major ingredient in car tyres. Silica is also used in plastics to impart flexural and compressive strenght.
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Water filtration |
Silica sand is the principal filtration medium used by the water industry to extract solid impurities from waste water.
Water industries in Europe use millions of tonnes of filtration sands each year.
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Agriculture |
Silica sand is used in farming, market gardening, horticulture, aquaculture, and forestry, in applications ranging from soil additive, surfacing material, and animal feed material.
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Sports and leisure facilities |
Silica sand with soil is used in the manufacture of football and other sports pitches and golf courses.
It is also used, often with polypropylene fibre or with rubber, for all-weather horse racing tracks, show jumping rings, dog racing tracks and equestrian training areas.
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Silicon metal and ferrosilicon production |
Quartz and the carbon reducing agents (wood, coal, coke, charcoal, electrodes) are put in an oven heated at a very high temperature (> 2000°C) thanks to an electric arc created through the electrodes. The metal is then cast, cooled and adapted according to the refining, granulometric and packaging specifications required by the customer.
In our daily lives, Silicon is the raw material for the following applications:
Silicones and silanes used for their waterproofness, for glues and mastics’ adhesion, for their insulating properties and for moulds’ production.
Iron and steel metallurgy: silicon is used to produce special up-market steels.
High-performance concrete: reinforcing concrete’s mechanical characteristics (e.g. resistance to compression).
Electronics: highly purified silicon gives birth to micro chips through high-tech and ultra automated processes.
Aluminium alloys: silicon increases the cast flow and the mechanical properties of aluminium alloys.
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Oil production |
Closely sized grades of silica sand, with rounded to sub rounded particles, are used to stimulate oil well production. The sand is pumped into the oil bearing strata and increases its permeability thereby promoting the flow of oil into the well.

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