| | Journal (article/letter/editorial) | NOVEMBER_DECEMBER, 1959 NOTES AND NEWS AN OCCURRENCEOF GENTHELVITE IN THE YOUNGERGRANITE PROVINCEOF NORTHERNNIGERIA*... voN KxonnrNct ar.rl P. Dvsowf INrnooucrroN Genthelvite, the zinc member of the helvite group is an extremely...(1953) and by Scott (1957).A notable amount of genthelvite has, however,recently beenfound by one of us...columbite-bearing membersof the Younger Granite suite in Northern Nigeria, and the occurrenceis of particular...beryllium mineral associated with the Nigerian Younger Granites, although beryl is not rare in the BasementComplex | | | Report (issue) | Genthelvite Zn4 Be3 (SiO4 )3 S c 2001 ° Mineral Data Publishing, version 1.2 Crystal Data: Cubic....Cu0:02 )§=3:99 Be2:91 Si2:97 O11:72 S1:00 : (2) Jos, Nigeria; corresponds to (Zn2:93 Fe2+ 0:96 Mn0:14 )§=4:03...Mountains, Ban®shire, Scotland. In the Jos-Bukuru complex, Nigeria. From the El Criollo pegmatite, Cerro...zinc-rich helvite (danalite), later renamed genthelvite. Type Material: Pennsylvania State University...elements, v. II, 119{126. (5) Dunn, P.J. (1976) Genthelvite and the helvine group. Mineral. Mag., 40, 627{636 | | | Journal (article/letter/editorial) | auhvolanic t o plutonic nature often in the form of ring complexes. These can be subdivided into two separate...by centres of ovcrsaturated magmatism such as Nigeria and Sudan. Thcre are also provinces with undersaturated...the abundance of zircon, uranium. thorium and complex Ti-Zr silicates, the importance o f columbite,...Geochemistry Mineralization Phanerozoic Cameron Niger Nigeria Sudan Saudi Arabia Namibia 1. Introduction Most...subvolcanic to plutonic nature often in the form of ring complexes. These can be subdivided into two separate | | | Journal (article/letter/editorial) | Canada H3A 0C4 peter.tarassoff@mail.mcgill.ca Genthelvite Mont Saint-Hilaire, Montérégie, Québec, Canada...helvine series. Any composition point in the genthelvite field in the diagram can be expressed as GenxDanyHevz...effectively the same as the molecular percents of genthelvite (Gen), danalite (Dan), and helvine (Hev). Reproduced...(fig. 2) set it apart from genthelvite from other localities. Genthelvite, ideally Be3Zn4(SiO4)3S, is...basis. A ternary composition Figure 2. Group of genthelvite crystals, to 5.1 cm on edge, with rhodochrosite | | | Journal (article/letter/editorial) | 60 Genthelvite and bertrandite .from the Cairngorm Mountains, Scotland By W. C. MORGAN, M.Sc., F.G.S...January 1967] Summary. A zinc-rich helvine (genthelvite) has been found with bertrandite in miarolitic...Coire an Lochain in the Cairngorm Mountains. The genthelvite occurs as green or brown tetrahedral crystals...In view of the extreme rarity of crystals of genthelvite, and the fact that the only previous records...with genthelvite or bertrandite. Genthelvite Previous discoveries. Three crystals of genthelvite, the | | | Book | George Obaje Geology and Mineral Resources of Nigeria 123 Prof. Nuhu George Obaje Nasarawa State University...University Dept. Geology & Mining Keffi Nigeria nobaje@yahoo.com ISSN 0930-0317 ISBN 978-3-540-92684-9...Resources of Nigeria are very few and mostly not accessible in Libraries and Bookshops in Nigeria. This book...activities in the Geology and Mineral Resources of Nigeria. The author has brought together several published...students of geology in tertiary institutions in Nigeria and abroad. Additional insights were also provided | | | Journal (volume) | Geochemistry of the Tioueine Pan-African Granite Complex (Hoggar, Algeria) : A. Azzouni-Sekkal and J . Boissonnas...Accessory Mineralogy of the Ririwai Biotite Granite, Nigeria, and its Albitized and Greisenized Facies: R. A...Magmatism, and Metamorphism in the Lower Benue Trough, Nigeria: J. Benkhelil ................... 467 A Model for...that the second event may be correlated with a younger orogeny possibly linking it to the Eburnean. ©...The oldest surrounding granitoids are coeval or younger than the supracrustals and both intrusive and | | | Book | AIr ring complexes and the chapter devoted to the Cameroon line. A detailed review of African ring complexes...discrimination between tholeiitic, transitional and alkaline ring complexes. Based on the available data (including...so-called alkaline intrusions which occur in African ring complexes are associated with tholeiitic or transitional...geochemical criteria discriminating the anorogenic ring complexes (including A - granites s.s.) from the...review our present knowledge of the main African ring complexes and emphasize the need for a new classification | | | Book | colour index. This is, without doubt, the most complex lithologie association to be handled from the point...ores are almost always "epigenetic", that is, younger than the adjacent rock and generally emplaced when...abundant, provide reservoirs to fluids generated by younger (often the youngest) phases that are usually volumetrically...or in the mine workings at all. The Climax Mo complex is the best known example. Here three generations...emplaced by large-scale magmatic stoping and as ring dikes or cone sheets. Additional characteristics | | | Book | colour index. This is, without doubt, the most complex lithologic association to be handled from the point...ores are almost always "epigenetic", that is, younger than the adjacent rock and generally emplaced when...abundant, provide reservoirs to fluids generated by younger (often the youngest) phases that are usually volumetrically...or in the mine workings at all. The Climax Mo complex is the best known example. Here three generations...emplaced by large-scale magmatic stoping and as ring dikes or cone sheets. Additional characteristics | | | Book (volume) | A. Bogatikov 199 The Ti hama Asir I gneous Complex , a passive marg i n ophiolite R. G. Coleman 22...upper part of the critical zone of the Bushveld complex and its bearing on the origin of the Merensky Reef...sorretirres appear , granite included (Jos plateau in Nigeria, White M:)untains massif in the Appalachians)...of the Basin and Range Province, and Col umbian plateau basalts associated with intraplate volcanism; 4)...influence of intraplate magmatism. This kind of complex environment, de.n oted as the M::)ngol-Okhotsk | | | Book (edition) | oxides and similar compounds, oxidic compounds with complex anions, and a few organic species. Mineral species...Subsidim-y anions (OH,F,O) are positioned before the complex anion , with both enclosed in square brackets,...of the valency electrons of the oxygens of the complex ions are involved in bonding to the cations". The...halides without H2O 3.B Simple halides with H2O 3.C Complex halides 3.D Oxyhalides, hydroxyhalides, and related...(groups of islands silicates) 9.C Cyclosilicates (ring silicates) 9.D Inosilicates (chain silicates) 9 | | | Journal (issue) | Lovozero-Massiv,Kola,Russland (ESKOVA 1957), Jos-Bukuru-Komplex, Nigeria (KNORRING & DYSON 1959), Cairngorm Mountains...139-145. BOLLINGBERG, H.; PETERSEN, 0 . V (1967): Genthelvite from the Ilimaussaq alkaline intrusion,South...(1976): Genthelvite and the helvine group. Mineral. Mag. 40, 627-636. ESKOVA,E.M.(1957): Genthelvite from... 163-191. HAAPALA, !.; OJANPERÄ, P. (1972): Genthelvite-bearing greisens in southern Finland. - Geological...(1959): An occurence of genthelvite in the Younger Granite Province of Northern Nigeria. -Amer. Mineral. 44 | | Gaines, Richard V., Skinner, H. Catherine W., Foord, Eugene E., Mason, Brian, Rosenzweig, Abraham, King, Vandall T. (1997) Dana's New Mineralogy (8th ed.) Wiley-Interscience. p.1872 | Book (edition) | and O, OH, F, and H20 Groups and Other Anions or Complex and Some Beryllosilicates 1020 1061 1106 1116...followed in this edition. The many and often very complex silicate minerals are here classified for the first...may be less for simple structures or more for complex ones. Typically, the projection is down the shortest...but ant predomin the to refers label The true. complex structures this may not be by species in a site...appearance of its surfaces in reflected light. It is a complex property that depends on a mineral’s reflectivity; | | | Book (edition) | (crystal class) designation; the latter may contain complex symmetry operations such as glide planes (instead...localities in Greenland, Scotland, Norway, USSR, Nigeria, Kenya, India, and elsewhere. SELECTED REFERENCE:...Pantelleria, Mediterranean Sea, in the Liruei Complex, Nigeria; and widespread in the rocks of East Africa...206•H20 Zeolite Group AMPHIBOLE GROUP A chemically complex group of orthorhombic or monoclinic double-chain...Thompsons, Grand County; in New Mexico as superb complex crystals over ½ inch in size encrusting sandstone | | | Book (edition) | (crystal class) designation; the latter may contain complex symmetry operations such as glide planes (instead...localities in Greenland, Scotland, Norway, USSR, Nigeria, Kenya, India, and elsewhere. SELECTED REFERENCE:...Pantelleria, Mediterranean Sea, in the Liruei Complex, Nigeria; and widespread in the rocks of East Africa...) CLEAVAGE: Not determined HABIT: Massive, in complex intergrowths; as small grains COLOR-LUSTER: Silver...Euxenite NaAlSi,O.°H,O AMPHIBOLE GROUP A chemically complex group of orthorhombic or monoclinic double-chain |
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