"saved up to 25% in the production of iron, and that the quality of the iron was also superior (Adams, “US Coal Industry”). By the 1850s anthracite was used in the manufacture of about half of all crude iron produced in the US. The increased efficiency of anthracite heat was also instrumental in the manufacture of metal machinery and the transformation of water into steam for machinery power (Dublin, Licht, 17). The Civil War created a shift in the makeup of the anthracite coal industry. Prior to the war, the industry involved many small-scale mines with short-term leases resulting in"
"the Anthracite locus. This darkens the body colour to a shade somewhat deeper than a Dark Green. The DF Anthracite Light Green, with two Anthracite alleles, is a deep olive colour. In the blue series varieties the SF Anthracite Skyblue has one Anthracite allele and one wild-type allele, with a body colour rather like a deep Cobalt. The DF Anthracite Skyblue with two Anthracite alleles, the true Anthracite variety, has a dark grey, almost black, body colour with mauve overtones. Because the Anthracite factor is always visibly expressed no budgerigar can be split for Anthracite. The heterozygotes of Anthracite with"
"Brucite Brucite is the mineral form of magnesium hydroxide, with the chemical formula Mg(OH). It is a common alteration product of periclase in marble; a low-temperature hydrothermal vein mineral in metamorphosed limestones and chlorite schists; and formed during serpentinization of dunites. Brucite is often found in association with serpentine, calcite, aragonite, dolomite, magnesite, hydromagnesite, artinite, talc and chrysotile. It adopts a layered CdI-like structure with hydrogen-bonds between the layers. Brucite was first described in 1824 and named for the discoverer, American mineralogist, Archibald Bruce (1777–1818). A fibrous variety of brucite is called nemalite. It occurs in fibers or laths, usually"
"magnesium attack and should be avoided. Brucite Brucite is the mineral form of magnesium hydroxide, with the chemical formula Mg(OH). It is a common alteration product of periclase in marble; a low-temperature hydrothermal vein mineral in metamorphosed limestones and chlorite schists; and formed during serpentinization of dunites. Brucite is often found in association with serpentine, calcite, aragonite, dolomite, magnesite, hydromagnesite, artinite, talc and chrysotile. It adopts a layered CdI-like structure with hydrogen-bonds between the layers. Brucite was first described in 1824 and named for the discoverer, American mineralogist, Archibald Bruce (1777–1818). A fibrous variety of brucite is called nemalite. It"
"Andesite Andesite ( or ) is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and rhyolite, and ranges from 57 to 63% silicon dioxide (SiO) as illustrated in TAS diagrams. The mineral assemblage is typically dominated by plagioclase plus pyroxene or hornblende. Magnetite, zircon, apatite, ilmenite, biotite, and garnet are common accessory minerals. Alkali feldspar may be present in minor amounts. The quartz-feldspar abundances in andesite and other volcanic rocks are illustrated in QAPF diagrams. Classification of andesites may be refined according to the"
"Anorthosite Anorthosite () is a phaneritic, intrusive igneous rock characterized by its composition: mostly plagioclase feldspar (90–100%), with a minimal mafic component (0–10%). Pyroxene, ilmenite, magnetite, and olivine are the mafic minerals most commonly present. Anorthosites are of enormous geologic interest, because it is still not fully understood how they form. Most models involve separating plagioclase crystals based on their density. Plagioclase crystals are usually less dense than magma; so, as plagioclase crystallizes in a magma chamber, the plagioclase crystals float to the top, concentrating there. Anorthosite on Earth can be divided into five types: Of these, the first two"
"power-generation. The rarer higher grades of anthracite are purer – i.e., they have a higher carbon content – and are used in steel-making and other segments of the metallurgical industries. Technical characteristics of the various grades of anthracite are as follows: Anthracite is divided by size mainly into applications that need lumps (typically larger than 10 mm) – various industrial processes where it replaces metallurgical coke, and domestic fuel – and those that need fines (less than 10 mm), such as sintering and pelletising. The common American classification by size is as follows: Lump, steamboat, egg and stove coals, the"
"types: the so-called 'anorthosite suite' or 'anorthosite-mangerite-charnockite-granite (AMCG) complex'. These rock types can include: Though co-eval, these rocks likely represent chemically-independent magmas, likely produced by melting of country rock into which the anorthosites intruded. Importantly, large volumes of ultramafic rocks are not found in association with Proterozoic anorthosites. Since they are primarily composed of plagioclase feldspar, most of Proterozoic anorthosites appear, in outcrop, to be grey or bluish. Individual plagioclase crystals may be black, white, blue, or grey, and may exhibit an iridescence known as labradorescence on fresh surfaces. The feldspar variety labradorite is commonly present in anorthosites. Mineralogically, labradorite"
"Andradite Andradite is a species of the garnet group. It is a nesosilicate, with formula CaFeSiO. Andradite includes three varieties: It was first described in 1868 for an occurrence in Drammen, Buskerud, Norway. Andradite was named after the Brazilian statesman, naturalist, professor and poet José Bonifácio de Andrada e Silva (1763–1838). It occurs in skarns developed in contact metamorphosed impure limestones or calcic igneous rocks; in chlorite schists and serpentinites and in alkalic igneous rocks (typically titaniferous). Associated minerals include vesuvianite, chlorite, epidote, spinel, calcite, dolomite and magnetite. It is found in Italy, the Ural Mountains of Russia, Arizona and"
"and GRA 06129) that were discovered in the Graves Nunataks icefield during the US Antarctic Search for Meteorites 2006/2007 field season. This possibly points to a new mechanism to generate andesite crust. Andesite Andesite ( or ) is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and rhyolite, and ranges from 57 to 63% silicon dioxide (SiO) as illustrated in TAS diagrams. The mineral assemblage is typically dominated by plagioclase plus pyroxene or hornblende. Magnetite, zircon, apatite, ilmenite, biotite, and garnet are common accessory"
"Anhydrite Anhydrite is a mineral—anhydrous calcium sulfate, CaSO. It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry. It is not isomorphous with the orthorhombic barium (baryte) and strontium (celestine) sulfates, as might be expected from the chemical formulas. Distinctly developed crystals are somewhat rare, the mineral usually presenting the form of cleavage masses. The Mohs hardness is 3.5 and the specific gravity is 2.9. The color is white, sometimes greyish, bluish, or purple. On the best developed of the three cleavages, the lustre is pearly; on other surfaces it"
"Omphacite Omphacite is a member of the pyroxene group of silicate minerals with formula: (Ca, Na)(Mg, Fe, Al)SiO. It is a variably deep to pale green or nearly colorless variety of pyroxene. Omphacite compositions are intermediate between calcium-rich augite and sodium-rich jadeite. It crystallizes in the monoclinic system with prismatic, typically twinned forms, though usually anhedral. Its space group (P2/n) is distinct from that of augite and jadeite (C2/c). It exhibits the typical near 90° pyroxene cleavage. It is brittle with specific gravity of 3.29 to 3.39 and a Mohs hardness of 5 to 6. It is a major mineral"
"Antarcticite Antarcticite is an uncommon calcium chloride hexahydrate mineral with formula: CaCl·6HO. It forms colorless acicular trigonal crystals. It is hygroscopic and has a low specific gravity of 1.715. As its name implies, it was first described in 1965 for an occurrence in Antarctica where it occurs as crystalline precipitate from a highly saline brine in Don Juan Pond, in the west end of Wright Valley, Victoria Land. This discovery was made by Japanese geochemists Tetsuya Torii and Joyo Ossaka. It was also reported from brine in Bristol Dry Lake, California, and stratified brine within blue holes on North Andros"
"Anthophyllite Anthophyllite is an amphibole mineral: ☐MgMgSiO(OH) (☐ is for a vacancy, a point defect in the crystal structure), magnesium iron inosilicate hydroxide. Anthophyllite is polymorphic with cummingtonite. Some forms of anthophyllite are lamellar or fibrous and are classed as asbestos. The name is derived from the Latin word ""anthophyllum"", meaning ""clove"", an allusion to the most common color of the mineral. Anthophylite is the product of metamorphism of magnesium-rich rocks, especially ultrabasic igneous rocks and impure dolomitic shales. It also forms as a retrograde product rimming relict orthopyroxenes and olivine, and as an accessory mineral in cordierite-bearing gneisses and"
"shades of green, beige, brown, gray, and blue, but in incandescent light, they appear a reddish or purplish/pink color. This is the rarest type of garnet. Because of its color-changing quality, this kind of garnet resembles Alexandrite. Andradite is a calcium-iron garnet, CaFe(SiO), is of variable composition and may be red, yellow, brown, green or black. The recognized varieties are topazolite (yellow or green), demantoid (green) and melanite (black). Andradite is found both in deep-seated igneous rocks like syenite as well as serpentines, schists, and crystalline limestone. Demantoid has been called the ""emerald of the Urals"" from its occurrence there,"
"Anglesite Anglesite is a lead sulfate mineral with the chemical formula PbSO. It occurs as an oxidation product of primary lead sulfide ore, galena. Anglesite occurs as prismatic orthorhombic crystals and earthy masses, and is isomorphous with barite and celestine. It contains 74% of lead by mass and therefore has a high specific gravity of 6.3. Anglesite's color is white or gray with pale yellow streaks. It may be dark gray if impure. It was first recognized as a mineral species by William Withering in 1783, who discovered it in the Parys copper-mine in Anglesey; the name anglesite, from this"
"Anthracene Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula CH, consisting of three fused benzene rings. It is a component of coal tar. Anthracene is used in the production of the red dye alizarin and other dyes. Anthracene is colorless but exhibits a blue (400–500 nm peak) fluorescence under ultraviolet radiation. Coal tar, which contains around 1.5% anthracene, remains a major source of this material. Common impurities are phenanthrene and carbazole. A classic laboratory method for the preparation of anthracene is by cyclodehydration of o-methyl- or o-methylene-substituted diarylketones in the so-called Elbs reaction. Anthracene photodimerizes by the action"
"Antlerite Antlerite is a greenish hydrous copper sulfate mineral, with the formula Cu(SO)(OH). It occurs in tabular, acicular, or fibrous crystals with a vitreous luster. Originally believed to be a rare mineral, antlerite was found to be the primary ore of the oxidised zones in several copper mines across the world, including the Chuquicamata mine in Chile, and the Antler mine in Arizona, US from which it takes its name. It is chemically and optically similar in many respects to other copper minerals such as malachite and brochantite, though it can be distinguished from the former by a lack of"
"Fornacite Fornacite is a rare lead, copper chromate arsenate hydroxide mineral with the formula: PbCu(CrO)(AsO)(OH). It forms a series with the phosphate mineral vauquelinite. It forms variably green to yellow, translucent to transparent crystals in the monoclinic - prismatic crystal system. It has a Mohs hardness of 2.3 and a specific gravity of 6.27. It was first described in 1915 and named after Lucien Lewis Forneau (1867–1930) the governor of the French Congo. Its type locality is in Reneville, Congo Republic. It occurs in the oxidized zone of ore deposits and is associated with dioptase, wulfenite, hemihedrite, phoenicochroite, duftite, mimetite,"
"meteorites classified as angrites. The type specimen, the Angra dos Reis meteorite, was an observed fall in 1869 and at is the fourth-heaviest angrite. The three largest are D'Orbigny (), ""Sahara 99555"" () and ""NWA 4931"" with . Angrite Angrites are a rare group of achondrites consisting mostly of the mineral augite with some olivine, anorthite and troilite. The group is named for the Angra dos Reis meteorite. Angrites are basaltic rocks, often having porosity, with vesicle diameters of up to . They are the oldest igneous rocks, with crystallization ages of around 4.55 billion years. By comparing the reflectance"
"Kamacite Kamacite is an alloy of iron and nickel, which is found on Earth only in meteorites. The proportion iron:nickel is between 90:10 and 95:5; small quantities of other elements, such as cobalt or carbon may also be present. The mineral has a metallic luster, is gray and has no clear cleavage although its crystal structure is isometric-hexoctahedral. Its density is about 8 g/cm and its hardness is 4 on the Mohs scale. It is also sometimes called balkeneisen. The name was coined in 1861 and is derived from the Greek root ""καμακ-"" ""kamak"" or ""κάμαξ"" ""kamaks"", meaning vine-pole. It"
"sodium, such as nepheline-syenite and phonolite. Pargasite is a rare magnesium-rich amphibole with essential sodium, usually found in ultramafic rocks. For instance, it occurs in uncommon mantle xenoliths, carried up by kimberlite. It is hard, dense, black and usually idiomorphic, with a red-brown pleochroism in petrographic thin section. Amphibole Amphibole () is an important group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Amphiboles can be green, black, colorless, white, yellow, blue, or brown. The International Mineralogical Association currently classifies"
"Analcime Analcime or analcite (from the Greek ""analkimos"" - ""weak"") is a white, gray, or colorless tectosilicate mineral. Analcime consists of hydrated sodium aluminium silicate in cubic crystalline form. Its chemical formula is NaAlSiO·HO. Minor amounts of potassium and calcium substitute for sodium. A silver-bearing synthetic variety also exists (Ag-analcite). Analcime is usually classified as a zeolite mineral, but structurally and chemically it is more similar to the feldspathoids. Analcime occurs as a primary mineral in analcime basalt and other alkaline igneous rocks. It also occurs as cavity and vesicle fillings associated with prehnite, calcite, and zeolites. Well known locations"
"Dacite Dacite () is an igneous, volcanic rock. It has an aphanitic to porphyritic texture and is intermediate in composition between andesite and rhyolite. The word dacite comes from Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains (now modern Romania and Moldova) where the rock was first described. Dacite consists mostly of plagioclase feldspar with biotite, hornblende, and pyroxene (augite and/or enstatite). It has quartz as some rounded, corroded phenocrysts, or as an element of the ground-mass. The relative proportions of feldspars and quartz in dacite, and in many other volcanic rocks,"
"Nephrite Nephrite is a variety of the calcium, magnesium, and iron-rich amphibole minerals tremolite or actinolite (aggregates of which also make up one form of asbestos). The chemical formula for nephrite is Ca(Mg, Fe)SiO(OH). It is one of two different mineral species called jade. The other mineral species known as jade is jadeite, which is a variety of pyroxene. While nephrite jade possesses mainly grays and greens (and occasionally yellows, browns or whites), jadeite jade, which is rarer, can also contain blacks, reds, pinks and violets. Nephrite jade is an ornamental stone used in carvings, beads, or cabochon cut gemstones."
"Lherzolite Lherzolite is a type of ultramafic igneous rock. It is a coarse-grained rock consisting of 40 to 90% olivine along with significant orthopyroxene and lesser calcic chromium-rich clinopyroxene. Minor minerals include chromium and aluminium spinels and garnets. Plagioclase can occur in lherzolites and other peridotites that crystallize at relatively shallow depths (20 – 30 km). At greater depth plagioclase is unstable and is replaced by spinel. At approximately 90 km depth, pyrope garnet becomes the stable aluminous phase. Garnet lherzolite is a major constituent of the Earth's upper mantle (extending to ~300 km depth). Lherzolite is known from the"
"Anorthite Anorthite is the calcium endmember of the plagioclase feldspar mineral series. The chemical formula of pure anorthite is CaAlSiO. Anorthite is found in mafic igneous rocks. Anorthite is rare on the Earth but abundant on the Moon. Anorthite is the calcium-rich endmember of the plagioclase solid solution series, the other endmember being albite, NaAlSiO. Anorthite also refers to plagioclase compositions with more than 90 molecular percent of the anorthite endmember. At 1 atmosphere, anorthite melts at 1553°C. Anorthite is a rare compositional variety of plagioclase. It occurs in mafic igneous rock. It also occurs in metamorphic rocks of granulite"
"Some gemstone varieties of labradorite exhibiting a high degree of labradorescence are called spectrolite. Labradorite Labradorite ((Ca, Na)(Al, Si)O), a feldspar mineral, is an intermediate to calcic member of the plagioclase series. It has an anorthite percentage (%An) of between 50 and 70. The specific gravity ranges from 2.68 to 2.72. The streak is white, like most silicates. The refractive index ranges from 1.559 to 1.573 and twinning is common. As with all plagioclase members, the crystal system is triclinic, and three directions of cleavage are present, two of which are nearly at right angles and are more obvious, being"
"Quartz monzonite Quartz monzonite or adamellite is an intrusive, felsic, igneous rock that has an approximately equal proportion of orthoclase and plagioclase feldspars. It is typically a light colored phaneritic (coarse-grained) to porphyritic granitic rock. The plagioclase is typically intermediate to sodic in composition, andesine to oligoclase. Quartz is present in significant amounts. Biotite and/or hornblende constitute the dark minerals. Because of its coloring, it is often confused with granite, but whereas granite contains more than 20% quartz, quartz monzonite is only 5–20% quartz. Rock with less than five percent quartz is classified as monzonite. A rock with more alkali"
"Anthodite Anthodites (Greek ἄνθος ""ánthos"", “flower”, ""-ode"", adjectival combining form, ""-ite"" adjectival suffix) are speleothems (cave formations) composed of long needle-like crystals situated in clusters which radiate outward from a common base. The ""needles"" may be quill-like or feathery. Most anthodites are made of the mineral aragonite (a variety of calcium carbonate, CaCO), although some are composed of gypsum (CaSO·2HO). The term ""anthodite"" is first cited in the scientific literature in 1965 by Japanese researcher N. Kashima, who described “flower-like dripstone” composed of “an alternation of calcite and aragonite”. The individual crystals of anthodites develop in a form described as"
"Andersonite Andersonite, NaCa(UO)(CO)·6HO, or hydrated sodium calcium uranyl carbonate is a rare uranium carbonate mineral that was first described in 1948. Named after Charles Alfred Anderson (1902–1990) of the United States Geological Survey, who first described the mineral species, it is found in sandstone-hosted uranium deposits. It has a high vitreous to pearly luster and is fluorescent. Andersonite specimens will usually glow a bright lemon yellow (or green with blue hints depending on the deposit) in ultraviolet light. It is commonly found as translucent small rhombohedral crystals that have angles close to 90 degrees although its crystal system is nominally"
"Variscite Variscite is a hydrated aluminium phosphate mineral (·2HO). It is a relatively rare phosphate mineral. It is sometimes confused with turquoise; however, variscite is usually greener in color. The green color results from the presence of small amounts of Chromium. Variscite is a secondary mineral formed by direct deposition from phosphate-bearing water that has reacted with aluminium-rich rocks in a near-surface environment. It occurs as fine-grained masses in nodules, cavity fillings, and crusts. Variscite often contains white veins of the calcium aluminium phosphate mineral crandallite. It was first described in 1837 and named for the locality of Variscia, the"
"Ardaite Ardaite is a very rare sulfosalt mineral with chemical formula PbSbSCl in the monoclinic crystal system, named after the Arda river, which passes through the type locality. It was discovered in 1978 and approved by the International Mineralogical Association in 1980. It was the second well-defined natural chlorosulfosalt, after dadsonite. Greenish gray or bluish green in color, its luster is metallic. Ardaite occurs as 50 µm fine-grained aggregates of acicular crystals associated with galena, pyrostilpnite, anglesite, nadorite, and Cl-bearing robinsonite and semseyite, in the Madjarovo polymetallic ore deposit in Bulgaria. Ardaite has a hardness of 2.5 to 3 on"