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Lorenzenite
Lorenzenite is a rare sodium titanium silicate mineral with the formula Na2 Ti2 Si2 O9 It is an orthorhombic mineral, variously found as colorless, grey, pinkish, or brown crystals. It was first identified in 1897 in rock samples from Narsarsuk, Greenland. In 1947 it was discovered to be the same as the mineral ramsayite (now a synonym of lorenzenite), discovered in the 1920s in the Kola peninsula of Russia. It is also found in northern Canada. It occurs in nepheline syenites and pegmatites in association with aegirine, nepheline, microcline, arfvedsonite, elpidite, loparite, eudialyte, astrophyllite, mangan-neptunite, lavenite, rinkite, apatite, titanite and ilmenite Ilmenite is a titanium-iron oxide mineral with the idealized formula . It is a weakly magnetic black or steel-gray solid. Ilmenite is the most important ore of titanium and the main source of titanium dioxide, which is used in paints, printing .... It was named in honor of Danish mineralogist Johannes Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lovozero Massif
The Lovozero Massif (russian: Ловозёрские тундры, ''Lovozyorskiye Tundry'', named after the lake in that area – Lake Lovozero; the region is also known as , ''Lovozyorye'') is a mountain range located in the center of the Kola Peninsula in Russia, between Lovozero and Lake Umbozero, and constitutes a horseshoe-shaped ridge of picturesque hills, that surround the Seydozero Lake. The slopes are covered mainly with spruce and pine. The highest point is Mount Angvundaschorr (1,120 m). The area around the lake is inhabited by Saami, and many place names are of non-Russian origin. Geology The Lovozero Massif is underlain by a complex of agpaitic to hyperagpaitic rocks containing minerals as eudialyte, loparite (an ore of niobium and tantalum), natrosilite (anhydrous sodium silicate), etc. At least 105 valid minerals have been described in the massif and 39 minerals were initially discovered there.http://www.mindat.org/loc-2689.html Mindat mineral list The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegirine
Aegirine is a member of the clino pyroxene group of inosilicate minerals. Aegirine is the sodium endmember of the aegirine- augite series. Aegirine has the chemical formula Na Fe Si2 O6 in which the iron is present as Fe3+. In the aegirine-augite series the sodium is variably replaced by calcium with iron(II) and magnesium replacing the iron(III) to balance the charge. Aluminium also substitutes for the iron(III). Acmite is a fibrous, green-colored variety. Aegirine occurs as dark green monoclinic prismatic crystals. It has a glassy luster and perfect cleavage. Its Mohs hardness varies from 5 to 6, and its specific gravity is between 3.2 and 3.4. This mineral commonly occurs in alkalic igneous rocks, nepheline syenites, carbonatites and pegmatites. It also appears in regionally metamorphosed schists, gneisses, and iron formations; in blueschist facies rocks, and from sodium metasomatism in granulites. It may occur as an authigenic mineral in shales and marls. It occurs in ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ilmenite
Ilmenite is a titanium-iron oxide mineral with the idealized formula . It is a weakly magnetic black or steel-gray solid. Ilmenite is the most important ore of titanium and the main source of titanium dioxide, which is used in paints, printing inks, fabrics, plastics, paper, sunscreen, food and cosmetics. Structure and properties Ilmenite is a heavy (specific gravity 4.7), moderately hard (Mohs hardness 5.6 to 6), opaque black mineral with a submetallic luster. It is almost always massive, with thick tabular crystals being quite rare. It shows no discernible cleavage, breaking instead with a conchoidal to uneven fracture. Ilmenite crystallizes in the trigonal system with space group ''R''. The ilmenite crystal structure consists of an ordered derivative of the corundum structure; in corundum all cations are identical but in ilmenite Fe2+ and Ti4+ ions occupy alternating layers perpendicular to the trigonal c axis. Pure ilmenite is paramagnetic (showing only very weak attrac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanite
Titanite, or sphene (from the Greek ''sphenos'' (σφηνώ), meaning wedge), is a calcium titanium nesosilicate mineral, Ca Ti Si O5. Trace impurities of iron and aluminium are typically present. Also commonly present are rare earth metals including cerium and yttrium; calcium may be partly replaced by thorium. Nomenclature The International Mineralogical Association Commission on New Minerals and Mineral Names (CNMMN) adopted the name titanite and "discredited" the name sphene as of 1982, although commonly papers and books initially identify the mineral using both names. Sphene was the most commonly used name until the IMA decision, although both were well known. Some authorities think it is less confusing as the word is used to describe any chemical or crystal with oxidized titanium such as the rare earth titanate pyrochlores series and many of the minerals with the perovskite structure. The name sphene continues to be publishable in peer-reviewed scientific literature, e.g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apatite
Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of OH−, F− and Cl− ions, respectively, in the crystal. The formula of the admixture of the three most common endmembers is written as Ca10( PO4)6(OH,F,Cl)2, and the crystal unit cell formulae of the individual minerals are written as Ca10(PO4)6(OH)2, Ca10(PO4)6F2 and Ca10(PO4)6Cl2. The mineral was named apatite by the German geologist Abraham Gottlob Werner in 1786, although the specific mineral he had described was reclassified as fluorapatite in 1860 by the German mineralogist Karl Friedrich August Rammelsberg. Apatite is often mistaken for other minerals. This tendency is reflected in the mineral's name, which is derived from the Greek word ἀπατάω (apatáō), which means ''to deceive''. Geology Apatite is very common as an accessory mineral in igneous and metamorphic rocks, where it is the most common phosphate mineral. However, occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neptunite
Neptunite is a silicate mineral with the formula K Na2 Li( Fe2+, Mn2+)2 Ti2 Si8 O24. With increasing manganese it forms a series with mangan-neptunite. Watatsumiite is the variety with vanadium replacing the titanium in the formula. It was first described in 1893 for an occurrence in the Narssârssuk pegmatite of West Greenland. It is also found within natrolite veins in glaucophane schist within serpentinite in San Benito County, California, US. It also occurs in Mont Saint-Hilaire, Quebec and in the Kola Peninsula of Russia. The mineral is named for Neptune, Roman god of the sea because of its association with aegirine from '' Àgir'', the Scandinavian sea-god. The Gemological Institute of America (GIA) identified an 11.78-carat faceted specimen as neptunite based on Raman spectroscopy Raman spectroscopy () (named after Indian physicist C. V. Raman) is a spectroscopic technique typically used to determine vibrational modes of molecules, although rotational and other low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrophyllite
Astrophyllite is a very rare, brown to golden-yellow hydrous potassium iron titanium silicate mineral. Belonging to the astrophyllite group, astrophyllite may be classed either as an inosilicate, phyllosilicate, or an intermediate between the two. It forms an isomorphous series with kupletskite, to which it is visually identical and often intimately associated. Astrophyllite is of interest primarily to scientists and collectors. Heavy, soft and fragile, astrophyllite typically forms as ''bladed'', radiating ''stellate'' aggregates. It is this crystal habit that gives astrophyllite its name, from the Greek words ''astron'' meaning " star" and ''phyllon'' meaning "leaf". Its great submetallic gleam and darkness contrast sharply with the light ( felsic) matrix the mineral is regularly found within. Astrophyllite is usually opaque to translucent, but may be transparent in thin specimens. As the crystals themselves possess perfect cleavage, they are typically left ''in situ'', the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eudialyte
Eudialyte, whose name derives from the Greek phrase , , meaning "well decomposable", is 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 was first described in 1819 for an occurrence in nepheline syenite of the Ilimaussaq intrusive complex of southwest Greenland. Uses of eudialyte Eudialyte is used as a minor ore of zirconium. Another use of eudialyte is as a minor gemstone, but this use is limited by its rarity, which is compounded by its poor crystal habit. These factors make eudialyte of primary interest as a collector's mineral. Eudialyte typically has a significant content of U, Pb, Nb, Ta, Zr, Hf, and rare earth elements (REE). Because of this, geoscientists use eudialyte as a geochronometer to date and investigate the genesis of the host rocks. Associated minerals Eudialyte is found associated with other alkalic igneous minerals, in addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 on polished thin section with reddish brown internal reflections.Loparite-(Ce) oWebmineral/ref> It has the chemical formula of . Nioboloparite is a variation of Loparite-(Ce) containing niobium. Loparite occurs as a primary phase in nepheline syenite intrusions and pegmatites. It is also found replacing perovskite in carbonatites. Loparite was first described for an occurrence in the Khibiny and Lovozero massifs, Kola peninsula in northern Russia. File:Loparite-crystal-structure-1.png , File:Loparite-crystal-structure-2.png , File:Loparite-crystal-structure-3.png , Etymology The term originates from the word ''Lopar'', the (former) Russian name for the Sami indigenous inhabitants of the Kola peninsula, and the cerium Cerium is a chemical element with the symbol Ce and atomic number 58. Cerium is a soft, ductile, and silv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
