Amazonite: Mineralogy, Crystal Chemistry, and Typomorphism
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LAB 3: COMMON MINERALS in SEDIMENTARY ROCKS, Part 1
EESC 2100: Mineralogy LAB 3: COMMON MINERALS IN SEDIMENTARY ROCKS, Part 1 Learning Objectives: Students will be able to identify minerals that occur commonly in sandstones (quartz and feldspars), both in hand-sample and thin-section Students will be able to determine the composition of plagioclase using the Michel-Levy method New Minerals: Quartz, Plagioclase, Microcline, Orthoclase Clastic sedimentary rocks are composed of grains that have been weathered from pre-existing rocks. The chemical weathering processes of hydrolysis, oxidation, and dissolution act on sediments, destroying those minerals that are most reactive, and forming new minerals that are stable at surface conditions: most halides and sulfates will dissolve; pyrite will form hydroxy-oxides such as limonite; unstable silicates will form clays. Minerals that are susceptible to physical weathering (i.e., minerals that are soft or cleavable) will be reduced in size during transport, and so may only be identified under the microscope. Quartz is a common rock-forming mineral, and resistant to both chemical and physical weathering. Accordingly, it is a common constituent of clastic sedimentary rocks. Feldspars are relatively stable in the surface environment, with potassium feldspars being more resistant to chemical weathering than plagioclase. Mafic minerals readily weather to form clays and iron hydroxy- oxides, and so are uncommon in sedimentary rocks. Thus the most important minerals in clastic sedimentary rocks are quartz, potassium feldspar (microcline and orthoclase), plagioclase, clays, and oxides/hydroxy-oxides (hematite, limonite, goethite). Percentages of quartz, feldspar, and clay are used to classify most clastic sedimentary rocks (sandstones, siltstones, claystones). QUARTZ Examine the four hand samples of quartz (Crystal, White, var. -
The Anjahamiary Pegmatite, Fort Dauphin Area, Madagascar
The Anjahamiary pegmatite, Fort Dauphin area, Madagascar Federico Pezzotta* & Marc Jobin** * Museo Civico di Storia Naturale, Corso Venezia 55, I-20121 Milano, Italy. ** SOMEMA, BP 6018, Antananarivo 101, Madagascar. E-mail:<[email protected]> 21 February, 2003 INTRODUCTION Madagascar is among the most important areas in the world for the production, mainly in the past, of tourmaline (elbaite and liddicoatite) gemstones and mineral specimens. A large literature database documents the presence of a number of pegmatites rich in elbaite and liddicoatite. The pegmatites are mainly concentrated in central Madagascar, in a region including, from north to south, the areas of Tsiroanomandidy, Itasy, Antsirabe-Betafo, Ambositra, Ambatofinandrahana, Mandosonoro, Ikalamavony, Fenoarivo and Fianarantsoa (e.g. Pezzotta, 2001). In general, outside this large area, elbaite-liddicoatite-bearing pegmatites are rare and only minor discoveries have been made in the past. Nevertheless, some recent work made by the Malagasy company SOMEMEA, discovered a great potential for elbaite-liddicoatite gemstones and mineral specimens in a large, unusual pegmatite (the Anjahamiary pegmatite), hosted in high- metamorphic terrains. The Anjahamiary pegmatite lies in the Fort Dauphin (Tôlanaro) area, close to the southern coast of Madagascar. This paper reports a general description of this locality, and some preliminary results of the analytical studies of the accessory minerals collected at the mine. Among the most important analytical results is the presence of gemmy blue liddicoatite crystals with a very high Ca content, indicating the presence in this tourmaline crystal of composition near the liddicoatite end-member. LOCATION AND ACCESS The Anjahamiary pegmatite is located about 70 km NW of the town of Fort Dauphin (Tôlanaro) (Fig. -
Bulletin of the Geological Society of America Vol. 56, Pp
BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA VOL. 56, PP. 50S-SI4, 4 PUS., 3 FIGS. MAY 1945 SIMPSONITE AND THE NORTHERN BRAZILIAN PEGMATITE REGION BY FREDERICK H. POUGH CONTENTS Page Abstract 505 Introduction and acknowledgments 505 General description of the Alto do Giz 506 Mineralogy 508 Simpsonite 508 Microlite 511 Tantalite and its varieties 512 Bismutite and cyrtolite 513 Paragenesis 513 References cited 514 ILLUSTRATIONS Figure Page 1.—Typical tabular yellow-brown Alto do Giz simpsonite crystal 510 2.—Minute tabular, buff-colored simpsonite from Onca Mine 510 3.—Prismatic crystal fragment from Onca Mine 510 Plate Facing page 1.—Simpsonite Frontispiece 2.—Alto do Giz ! 506 3.—Kaolinite replacements 507 4.—Microlite and cyrtolite 510 ABSTRACT A study of the Alto do Giz, near Equador, Rio Grande do Norte, Brazil, reveals an interesting series of tantalum minerals including the rare aluminum tantalate, simpsonite. Crystals of this mineral are yellow brown, hexagonal in outline; c = .60978. It belongs to the hexagonal dipyramidal class Ceh. Hardness 7J, specific gravity is 6.81. It fluoresces blue to white in a cold quartz mercury vapor lamp with a filter. It is also found in white crystals at this mine and in buff-colored crystals at the Onca Mine, some miles away. It appears to be a replacement mineral of a short complex pegmatite sequence, crystallizing after microlite and tantalite. INTRODUCTION AND ACKNOWLEDGMENTS The extensive exploitation of the numerous pegmatite operations in northern Brazil is a relatively recent development, since the beginning of the war. In the years immediately preceding, when some nations foresaw a need for stockpiles of raw materials, there was a certain amount of beryl and tantalite production in the region, but the real impetus to the development of this desert area was supplied by the advent of the United States Purchasing Commission and their introduction of various 505 Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/56/5/505/3425995/i0016-7606-56-5-505.pdf by guest on 28 September 2021 506 F. -
Mineral Processing
Mineral Processing Foundations of theory and practice of minerallurgy 1st English edition JAN DRZYMALA, C. Eng., Ph.D., D.Sc. Member of the Polish Mineral Processing Society Wroclaw University of Technology 2007 Translation: J. Drzymala, A. Swatek Reviewer: A. Luszczkiewicz Published as supplied by the author ©Copyright by Jan Drzymala, Wroclaw 2007 Computer typesetting: Danuta Szyszka Cover design: Danuta Szyszka Cover photo: Sebastian Bożek Oficyna Wydawnicza Politechniki Wrocławskiej Wybrzeze Wyspianskiego 27 50-370 Wroclaw Any part of this publication can be used in any form by any means provided that the usage is acknowledged by the citation: Drzymala, J., Mineral Processing, Foundations of theory and practice of minerallurgy, Oficyna Wydawnicza PWr., 2007, www.ig.pwr.wroc.pl/minproc ISBN 978-83-7493-362-9 Contents Introduction ....................................................................................................................9 Part I Introduction to mineral processing .....................................................................13 1. From the Big Bang to mineral processing................................................................14 1.1. The formation of matter ...................................................................................14 1.2. Elementary particles.........................................................................................16 1.3. Molecules .........................................................................................................18 1.4. Solids................................................................................................................19 -
Mineralogy and Geology of the \Vkgnerite Occurrence Co Santa Fe Mountain, Front Range, Cobrado
Mineralogy and Geology of the \Vkgnerite Occurrence co Santa Fe Mountain, Front Range, Cobrado GEOLOGICAL SURVEY PROFESSIONAL PAPER 955 Mineralogy and Geology of the Wignerite Occurance on Santa Fe Mountain, Front Range, Colorado By DOUGLAS M. SHERIDAN, SHERMAN P. MARSH, MARY E. MROSE, and RICHARD B. TAYLOR GEOLOGICAL SURVEY PROFESSIONAL PAPER 955 A detailed mineralogic study of wagnerite, a rare phosphate mineral occurring in the report area in Precambrian gneiss; this is the first recorded occurrence of wagnerite in the United States UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1976 UNITED STATES DEPARTMENT OF THE INTERIOR THOMAS S. KLEPPE, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress Cataloging in Publication Data Main entry under title: Mineralogy and geology of the wagnerite occurrence on Santa Fe Mountain, Front Range, Colorado. (Geological Survey Professional Paper 955) Includes bibliographical references. 1. Wagnerite Colorado Santa Fe Mountain. 2. Geology Colorado Santa Fe Mountain. I. Sheridan, Douglas M., 1921- II. Series: United States Geological Survey Professional Paper 955. QE391.W3M56 549'.72 76-10335 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, B.C. 20402 Stock Number 024-001-02844-1 CONTENTS Page Metric-English equivalents .............................. Descriptive mineralogy Continued Page Abstract............................................................ 1 Wagnerite............................................... 5 Introduction.................................................... -
Contributions to the Mineralogy of Norway
NORSK GEOLOGISK TIDSSKRIFT CONTRIBUTIONS TO THE MINERALOGY OF NORWAY No. 5. Trace element variations in three generations of felds pars from the Landsverk I pegmatite, Evje, southern Norway. BY S. R. TAYLOR l, K. S. HEIER 2 and T. L. SvERDRUP3 A bstract: Li, Na, K, Rb, Cs, Pb, Tl, Ca, Sr and Ba have been determined in potassium feldspars and coexisting albites of three different generations from one large pegmatite (Landsverk I, Evje, southern Norway). In additio n Fe, Cr, Mn, Cu, Co, Ni, V, Sn and F were determined in a pink microcline and a green amazonite which were seen to grade into each other. Same element concentrations and ratios reflect the different conditions of formation of the feldspars fro m the three generations. The data indicate that the amazonite formed through metasomatic action of a "pegmatitic rest liquid" (fro m which cleavelandite crystallised) on the pink microcline of the first gene ration. The trace element data also indicate that the youngest K- feldspar is no t a late fractio nation product of the pegmatite, but rather a late seco ndary mineralisati on. The cause of the colouring of the amazonite is discussed and it is concluded that it is not to be found in a signi fi cant difference in compositio n fro m the pink mi crocline for any of the elements determined. lntroduction. Two of the authors (K. S. H. and S. R. T.) have made previously an extensive study of the distribution of trace elements in K-feld spars from a variety of pre-Cambrian basement rocks from southern Norway (TAYLOR and HEIER; 1958 a, b, 1960; HEIER and TAYLOR, l Dept. -
And Ta-Bearing Oxide Minerals in the Greer Lake Pegmatitic Granite and Its Pegmatiteaureole, Southeasternmanitoba
American Mineralogist, Volume 71, pages 501-517, 1986 Fractionation trends of the Nb- and Ta-bearing oxide minerals in the Greer Lake pegmatitic granite and its pegmatiteaureole, southeasternManitoba Pnrn ennmi, Bnucn E. Golo,r FuNx C. H,lwruronNr, RoN CrHplr,lN Department of Earth Sciences,University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada Arsrucr The Greer Lake pegmatitic granite and related exterior rare-element pegmatites of the beryl-columbite type intrude metabasalt and tonalite gneiss in the Archean English River Subprovince of southeasternManitoba. Columbite-tantalite is the predominant Nb- and Ta-bearingmineral, associatedwith subordinateixiolite, microlite, niobian-tantalian rutile, and rare tantalian cassiterite, wodginite, and ilmenite. In coexisting mineral pairs, Tal(Ta + Nb) of microlite exceedsthat of columbite-tantalite, ixiolite, rutile, and cassiterite;in cassiteriteand rutile, Tal(Ta + Nb) is higher and Mn/(Mn * Fe) lower than in columbite- tantalite and ixiolite. In Li-, Rb-, Cs-, and F-poor environments, limited Mn enrichment accompaniesthe fractionation of Ta, which culminates in ixiolite and subordinate microlite. In Li-, Rb-, Cs-, and F-rich parageneses,extensive Mn enrichment precedesthe main Ta fractionation, which subsequentlygenerates near-end-member manganotantalite, wodginite, and mi- crolite. The Greer Lake and other fractionation trends indicate that a late-stageF-rich environment promotes extreme Fe/Mn fractionation prior to the main stage of Nb-Ta separation. The abundancesof Sn, Ti, and Sc are not related to fluorine or rare-alkali enrichment, but increasefrom pegmatitic granite to pegnatites. The relative accumulation of Ti and Sc in the pegmatite aureole seemsto be due to internal fractionation rather than assimilation. Columbite-tantalite in the pegmatitic granite shows an intermediate to near-ordered structural state, but is highly disordered in the pegmatite veins. -
Cesstibtantite Cs(Sb3+
3+ Cesstibtantite Cs(Sb , Na)Ta2(O, OH, F)7 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Cubic. Point Group: 4/m 32/m. As cubo-octahedral crystals; granular, to 3 mm. Physical Properties: Fracture: Uneven. Tenacity: Brittle. Hardness = ∼5 VHN = 670– 780 (100 g load). D(meas.) = 6.4–6.6 D(calc.) = 6.49 Fluoresces yellow-orange to orange under LW UV; weak yellowish cathodoluminescence. Optical Properties: Transparent; may be opaque except in thinnest fragments. Color: Colorless to gray, yellow-orange, black. Luster: Adamantine to vitreous. Optical Class: Isotropic. n = > 1.8 R: (480) 13.8, (551) 13.6, (589) 13.6, (656) 13.0 Cell Data: Space Group: Fd3m. a = 10.496–10.515 Z = 8 X-ray Powder Pattern: Kola Peninsula, Russia. 3.04 (10), 1.860 (10), 1.587 (10), 1.012 (10), 3.17 (9), 1.370 (9), 1.017 (9) Chemistry: (1) (2) (3) (1) (2) (3) Nb2O5 2.3 2.8 1.2 CaO 0.1 0.6 Ta2O5 72.0 70.8 72.5 Na2O 1.3 1.7 2.4 Bi2O3 0.7 0.3 0.6 K2O 0.0 0.05 Sb2O3 13.6 14.2 9.7 Cs2O 7.3 7.4 5.4 SnO 0.1 H2O [1.5] [1.2] PbO 1.6 0.8 5.3 Total 98.9 [99.5] [99.0] (1) Kola Peninsula, Russia; by electron microprobe, average of five analyses; (OH)1− confirmed by IR. (2) Do.; by electron microprobe, H2O calculated from structural considerations; corresponds to [Cs0.31(OH, F)0.69]Σ=1.00(Sb0.57Na0.31Pb0.02Bi0.01)Σ=0.91(Ta1.88Nb0.12)Σ=2.00 [O5.69(OH, F)0.31]Σ=6.00. -
Thirty-Fourth List of New Mineral Names
MINERALOGICAL MAGAZINE, DECEMBER 1986, VOL. 50, PP. 741-61 Thirty-fourth list of new mineral names E. E. FEJER Department of Mineralogy, British Museum (Natural History), Cromwell Road, London SW7 5BD THE present list contains 181 entries. Of these 148 are Alacranite. V. I. Popova, V. A. Popov, A. Clark, valid species, most of which have been approved by the V. O. Polyakov, and S. E. Borisovskii, 1986. Zap. IMA Commission on New Minerals and Mineral Names, 115, 360. First found at Alacran, Pampa Larga, 17 are misspellings or erroneous transliterations, 9 are Chile by A. H. Clark in 1970 (rejected by IMA names published without IMA approval, 4 are variety because of insufficient data), then in 1980 at the names, 2 are spelling corrections, and one is a name applied to gem material. As in previous lists, contractions caldera of Uzon volcano, Kamchatka, USSR, as are used for the names of frequently cited journals and yellowish orange equant crystals up to 0.5 ram, other publications are abbreviated in italic. sometimes flattened on {100} with {100}, {111}, {ill}, and {110} faces, adamantine to greasy Abhurite. J. J. Matzko, H. T. Evans Jr., M. E. Mrose, lustre, poor {100} cleavage, brittle, H 1 Mono- and P. Aruscavage, 1985. C.M. 23, 233. At a clinic, P2/c, a 9.89(2), b 9.73(2), c 9.13(1) A, depth c.35 m, in an arm of the Red Sea, known as fl 101.84(5) ~ Z = 2; Dobs. 3.43(5), D~alr 3.43; Sharm Abhur, c.30 km north of Jiddah, Saudi reflectances and microhardness given. -
Niobian Rutile from the Mcguire Granitic Pegmatite, Park County, Colorado: Solid Solution, Exsolution, and Oxidation
American Mineralogist, Volume 84, pages 754–763, 1999 Niobian rutile from the McGuire granitic pegmatite, Park County, Colorado: Solid solution, exsolution, and oxidation PETR Cˇ ERNY´ ,1,* RON CHAPMAN,1 WILLIAM B. SIMMONS,2 AND LEONARD E. CHACKOWSKY1 1 Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada 2 Department of Geology and Geophysics, University of New Orleans, New Orleans, Louisiana 70148-2850, U.S.A. ABSTRACT Coarse crystals of niobian rutile occur in the hydrothermally altered core-margin zone of the McGuire granitic pegmatite, Park County, Colorado, associated with potassium feldspar, quartz, bi- otite, ilmenite, and monazite-(Ce). Primary homogeneous niobian rutile, with Fe3+ @ Fe2+ and a small excess of (Fe,Mn) over the amount required to compensate the incorporation of (Nb,Ta,W), under- went three stages of exsolution. Primary homogeneous niobian rutile exsolved a fine trellis-like pat- tern of minor lamellar Nb-bearing pseudorutile I. Most of this phase was broken down to pseudomor- phs consisting of microgranular Nb-rich pseudorutile II imbedded in niobian-ferrian “ferropseudobrookite.” Continued exsolution in niobian rutile and reconstitution of the early exsolution products generated (Fe,Nb)-depleted, microgranular niobian rutile, titanian ferrocolumbite, and mi- nor ilmenite. These three phases did not attain chemical equilibrium but may represent a stable phase assemblage. All these processes seem to have maintained charge balance, suggesting a closed sys- tem. Subsequent to the three stages of exsolution, extensive oxidation converted the mineral assem- blages to anatase + hematite + titanian-tungstenian ixiolite; primary ilmenite was oxidized into an anatase + hematite intergrowth. In both cases, the hematite component was almost completely leached out, leaving highly porous aggregates of the other phases. -
Topographical Index
997 TOPOGRAPHICAL INDEX EUROPE Penberthy Croft, St. Hilary: carminite, beudantite, 431 Iceland (fsland) Pengenna (Trewethen) mine, St. Kew: Bondolfur, East Iceland: pitchsbone, beudantite, carminite, mimetite, sco- oligoclase, 587 rodite, 432 Sellatur, East Iceland: pitchs~one, anor- Redruth: danalite, 921 thoclase, 587 Roscommon Cliff, St. Just-in-Peuwith: Skruthur, East Iceland: pitchstonc, stokesite, 433 anorthoclase, 587 St. Day: cornubite, 1 Thingmuli, East Iceland: andesine, 587 Treburland mine, Altarnun: genthelvite, molybdenite, 921 Faroes (F~eroerne) Treore mine, St. Teath: beudantite, carminite, jamesonite, mimetite, sco- Erionite, chabazite, 343 rodite, stibnite, 431 Tretoil mine, Lanivet: danalite, garnet, Norway (Norge) ilvaite, 921 Gryting, Risor: fergusonite (var. risSrite), Wheal Betsy, Tremore, Lanivet: he]vine, 392 scheelite, 921 Helle, Arendal: fergusonite, 392 Wheal Carpenter, Gwinear: beudantite, Nedends: fergusonite, 392 bayldonite, carminite, 431 ; cornubite, Rullandsdalen, Risor: fergusonite, 392 cornwallite, 1 Wheal Clinton, Mylor, Falmouth: danal- British Isles ire, 921 Wheal Cock, St. Just-in- Penwith : apatite, E~GLA~D i~D WALES bertrandite, herderite, helvine, phena- Adamite, hiibnerite, xliv kite, scheelite, 921 Billingham anhydrite mine, Durham: Wheal Ding (part of Bodmin Wheal aph~hitalite(?), arsenopyrite(?), ep- Mary): blende, he]vine, scheelite, 921 somite, ferric sulphate(?), gypsum, Wheal Gorland, Gwennap: cornubite, l; halite, ilsemannite(?), lepidocrocite, beudantite, carminite, zeunerite, 430 molybdenite(?), -
The Stability of Danalite, Feober(Sior3s Donero M. Bunr
American Mineralogist, Volume 65, pages 355-360, 1980 The stability of danalite, FeoBer(SiOr3S DoNero M. Bunr Department of Geology, Arizona State University Tempe,Arizona 85281 Abstract End-memberdanalite is compositionallyequivalent to a mixture of pyrrhotite, phenakite, and fayalite, but danalite's natural occurrenceswith pyrite, magnetite,and quartz suggest that it is stable under somewhat more sulfidizing conditions than pyrrhotite and more oxidiz- ing conditions than fayatte. Danalite tends not to occur with hematite. Thesefacts can be usedto constructa tentative log /",-log f o,diagtan for the stability of the end member. The diagram shows that danalite, if it is stable at all, has an extremely narrow stability field cen- tered near the pyrrhotite,/magnetitefield boundary. Outside this field, phenakite (or, at low temperatures,bertrandite) is stablewith magnetite,pyrrhotite (or pyrite), and quartz. A natu- ral example of theseequilibria apparently occurs at Iron Mountain, Bartlett, New Hamp- shire, where zoned danalite-helvite solid solutions occur as overgrowths on phenakite with magnetite,pyrite, and quartz. Danalite is the only end memberof the helvite group that is appreciablysensitive to hypo- gene oxidation. The Mn and Zn end,members helvite and genthelviteare instead sensitive only to S-O exchange(variation in log /",//",). Introduction 2 FeoBe,(SiOo)rS:2 FeS+ 3 Be,SiOo+ 3 FerSiOo Danalite, FeoBer(SiOo)rS,is a rare beryllium ore danalite: troilite * phenakite* fayalite mineral in iron-rich skarns,greisens, and related me- Troilite (Tr) is not a common terrestrial phase; for tasomaticrocks (Glasset al., 19441,Beus, 1966; Dunn, the purposesofthis discussionit can be replacedby 1976). lt typically contains considerable helvite, pyrrhotite, Fe,-,S.