 | | Journal (article/letter/editorial) | | deposits in the Fort Victoria schist belt, in the Umvuma and Umtali-Odzi schist belts. slumping textures...schists. Very interesting is the Scheelite Valley Mine. Here 4--8 m thick, flat dipping scheelite skarn...in the eastern extension at the Edmundian Copper Mine east of Umtali as minor constituent. a) In the...Beardmore Mine) scheelite occurs in skarns, which eventually end up into limestone. In this mine the scheelite...banded jaspilites. b) In the Umvuma schist belt (AthensFalcon Mine, East Rand Mine, Iron Hill) in similar horizons |  | | Journal (article/letter/editorial) | | tectonism. Two principaltypesof veinsoccurin the mine; subverticalveinsand subhorizontalveins. They are...Lamaqueproperty(another major gold producerin the district),mostof theveinsat Sigmaarerestrictedto a blockof...deepandis the principalsubject of the followingreport. Mine Geology 76 ø Rock types • I [ Vald'Orl 48ø...porphyriticdioritewasemplacedpriorto regional the bottom of the mine. In addition to this metamordeformation. phismp...thesetwo rocktypesin Figure3 probably gioclase,quartz,chlorite,epidote,clinozoisite,white resultsin part |  | | Report (issue) | | interest in the geo logy and mineral resources of Zimbabwe which followed the removal of United Nations sanctions...original Bulletin is the insertion of Table IIIA, Zimbabwe Mineral Production and Value, on page 114A. Due...for views of Wankie Colliery and the Trojan nickel mine, and to the Photographic Section of the Ministry...near Salisbury. facing page 23 IV Trojan Nickel Mine, near Bindura. facing page 33 V The Great Dyke...Complex. VI Chrome seam in the Great Dyke, Vanad Mine. VII Lower Karoo Landscape. No. 1 Colliery, Wankie |  | | Report (volume) | | Blenkinsop examine Archaean deformation patterns in Zimbabwe and the adjacent Limpopo Belt and discuss the...Stratigraphic and tectono-stratigraphic problems in Zimbabwe and Western Australia are described in the next...mineralization in the Kadoma region of the Zimbabwe Midlands. Three papers describe the structures of the...:INSOP,T. G. Archaean deformation patterns in Zimbabwe: true indicators of Tibetan style crustal extension...geochronology of Archaean felsic sequences in the Zimbabwe craton: a revision of greenstone stratigraphy |  | | Journal (article/letter/editorial) | | Sector of Mashava Igneous Complex in south central Zimbabwe from an investigation of its silicate minerals...Sector of Mashava Igneous Complex in south central Zimbabwe from an investigation of its silicate minerals...Sector of Mashava Igneous Complex in south central Zimbabwe from an investigation of its silicate minerals...economically important Mashava Igneous Complex (MIC) in Zimbabwe was conducted using petrographic and silicate...and olivine. Spinel, sulfide minerals, and minor quartz as well as other opaque minerals are also present |  | | Journal (issue) | | Shepherd, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - 1 . Knight, Scottish...News, 9, 10--11 Van Praagh, G., 1947. Synthetic quartz crystals. Geological Magazine, 84, 98-100 Walrafen...and Burke, E.AJ., 1998. Emeralds from Sandawana, Zimbabwe: the use of Raman microspectroscopy in identification...other countries (e.g. Brazil, Russia, Zambia, Zimbabwe-Sandawana, Afghanistan and India) crystalline...and China. Eleven single crystals from Heffernan's mine, Torrington, New South Wales, Australia, five from |  | | Journal (issue) | | Shepherd, P.J. Wates, CH. Winter Branch Chairmen: Midlands - G.M. Green, North West - 1. Knight, Scottish...October 1998 ISSN: 1355-4565 Blue euclase from Zimbabwe—a review Susan Stocklmayer (née Anderson), FGS...ABSTRACT: Blue euclase from Mwame, Hurungwe District, Zimbabwe, which was first collected in the late 1970s...photomicrographs. Keywords: euclase, inclusions, pegmatite, Zimbabwe Euclase in Africa Introduction 174 uclase...beryllium minerals in a variety of host rocks, usually quartz veins, granitic pegmatites or greisens. Although |  | | Journal (issue) | | Read, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - D. M. Brady, Scottish...confirmed by Raman spectroscopy. Mogánite and α-quartz form part of the chalcedony matrix. Mtorolite,...variety of chrome chalcedony first described from Zimbabwe, was used for comparison. Keywords: chrome chalcedony...uniform deep green hue. When traversed by later quartz veins the colour grades to brown. spectroscopy...occurrences of chrome chalcedony, notably those in Zimbabwe and Bolivia (Smith, 1967: Hyrsl, 1999). Location |  | | Journal (issue) | | Read, R Shepherd, CH. Winter Branch Chairmen: Midlands - G.M. Green, North West - I. Knight, Scottish...China ABSTRACT: The turquoise deposit in Yunyang district, Hubei Province, China, is characterized by its...turquoise and its irregular occurrence in this district have attracted little attention from the Government...investigation into the turquoise mineralogy in this district and on the basis of this it was evident that more...siliceous slates, carbonaceous mica quartz rocks, calcareous mica quartz-schists and carbonaceous clay marbles |  | | Journal (issue) | | A. W. Hodgkinson C. H. Winter Branch Chairmen: Midlands Branch: C. L. Hundy, F.G.A. North-West Branch:...Franks, B.Sc., Ph.D., F.G.A. South Yorkshire & District Branch: J. I. Platts, F.G.A. Examiners: A. J....green beryl occur sporadically in talccarbonate-quartz rocks near Bucha (34° 24 W N, 71° 36' E). The host...epidote, garnet (red, green and honey), amethyst, quartz, and green diopside. Ornamental stones such as...in ultramafic rocks. Such rocks and associated quartz veins also host emerald and, in one place, a green |  | | Journal (issue) | | D. Warren C H . Winter, FGA Branch Chairmen: Midlands Branch: D.M. Larcher, FBHI, FGA North-West Branch:...specimens the authors have examined were colourless quartz crystals with man-made 'threephase' inclusions...what appeared to be a mixture of epoxy resin and quartz fragments (Koivula and Kammerling, 1989). In 1986...large rubellite crystals were found in the pegmatite mine at Sakangyi. Furthermore, Bauer (Spencer transi...result of a several weeks stay at Matara, which gem district he visited in response to an urgent request for |  | | Journal (article/letter/editorial) | | data of BIFs from the greenstone terranes of the Zimbabwe and Kaapvaal cratons. The study revealed that...consisting of alternating thin layers of chert (quartz) and iron minerals (iron-oxides, -carbonates, -silicates...geochemistry of some BIF-hosted gold deposits in Zimbabwe and considers mineralogical and geochemical aspects...greenstone belts of the Kaapvaal and the adjacent Zimbabwe cratons (Fig. 1). The two cratons are separated...previously (Fripp 1976, Fos- S 126 BROOMSTOCK MINE _~7-" ZIMB,ABWE CRATON Distribution of ] ore zones |  | | Journal (issue) | | Velden D. Warren C.H. Winter, FGA Branch Chairmen: Midlands Branch: D.M. Larcher, FBHI, FGA North-West Branch:... 22, 5 'Machingwe': A new emerald deposit in Zimbabwe Jan Kanis*, Charles E.S. Arps** and Pieter C....in the Mweza Range Greenstone Belt of southern Zimbabwe are discussed and compared with data from Sandawana...visit to a newly discovered emerald occurrence in Zimbabwe, named 'Machingwe deposit', thanks to the kind...assistance of the Mineral Marketing Corporation of Zimbabwe. This Corporation is a state controlled department |  | | Journal (issue) | | Read, R Shepherd, CH. Winter Branch Chairmen: Midlands ~ G.M. Green, North West -I. Knight, Scottish...areas) and drainages, Pailin district, Figure 2: Distribution district, continuous lines, with with gem-barren...and 7.9.3 member compositions). Thailand (Rubywell Mine) alluvial sapphirines (T) and NSW granulite-hosted...Gunawardene, M., 1985. Peridot from Ratnapura District, studies on crystallized silicate melt and other...of the year. In general about 30 people work each mine using picks and shovels, but at some, such as at |  | | Report (issue) | | Gold-antimony deposits are associated with low-sulfide gold-quartz vein deposits that occur in deformed metamorphic................... 19 ABSTRACT Gold-stibnite-quartz vein deposits and stratiform disseminated-veined...(940-1000 fineness), aurostibite in metamorphosed quartz-carbonate vein in compressive shear zones in low-grade...belts. The veins are similar to low sulfide gold-quartz veins but are very rich in sulfides, especially...talc-chlorite, talc-carbonate, quartz-chloritecarbonate schists, and slate; in quartz-feldspathic rocks, mainly |  | | Journal (issue) | | Shepherd, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - I. Knight, Scottish...addition of material baffle,7 7== nutrient, 8 quartz = quartz plates, = growing crystals, = lithium molybdat...Above this baffle, quartz plates of 8 to 10 mm in thickness were arranged. These quartz plates floated on...SCHIST ® Booyo Nokok M.inc (*sry) Booyo Nokok Mine serpentine A study of of Korean Koreanprecious...Non-precious extracted from the mine. the Booyo BooyoNokok Nokok mine. from (Chogyeri Formation) and sandstone |  | | Journal (issue) | | Read, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - D. M. Brady, Scottish...networks. 321 Introduction A steriated quartz, especially rose quartz, has been known for more than a century...of the quartz crystals. Rarely, twelve-rayed stars are also observed in quartz or rose quartz (Cassedanne...Figure 1). Occasionally, complete spheres of rose quartz show additional, mostly weak light bands that are...Sphere of very lightly coloured Brazilian rose quartz revealing twelve-rayed asterism. The diameter of |  | | Journal (issue) | | Roberts, R Shepherd, CH. Winter Branch Chairmen Midlands: J.W. Porter North West: 1. Knight Scottish: J... Cover Picture Faceted sapphire from Cyangugu district, SW Rwanda. See Investigations on sapphires from...Sapphires have been discovered in the Cyangugu district in south-west Rwanda (bordering Zaire) and details...discovered in 1917 the deep blue beryls from the Maxixe mine in Brazil have been a source of fascination both...Natrolite Petalite Leucite Oligoclase Quartz Synthetic quartz Iolite Scapolite Labradorite Beryl 2.91 |  | | Journal (issue) | | daylight-fluorescent opal from Mexico|‘Trapiche’ quartz with radiating fibres|Yellow scheelite from Pakistan|Spessartine...J. Wells, Stephen Whittaker Branch Chairmen Midlands – Georgina E. Kettle North East – Mark W. Houghton... Practical Gemmology Figure 2: The B/D ratio of quartz is 0.6, which corresponds to the 60% overlap in...available. The transparent quartz varieties of amethyst, citrine, smoky quartz and rock crystal are easily...B/D ratio of quartz (0.6), but what exactly does this number convey? When a faceted quartz is observed |  | | Journal (issue) | | Geological Society of Zimbabwe Newsletter June, 2008 Geological Society of Zimbabwe G Z S Newsletter...SOCIETY OF ZIMBABWE, P.O. BOX CY 1719, CAUSEWAY, HARARE Geological Society of Zimbabwe Newsletter ...……………………………………………….. 5 Geology of the Chewore Inliers, Zimbabwe: Constraining the Mesoproterozoic to Palaeozoic...Triassic/EarlyJurassic Forest Sandstone, Mana Pools Basin, Zimbabwe ..…………. 9 AGM - CHAIRMAN’S REPORT 2007………………………………………………………...Honorary Life Membership of the Geological Society of Zimbabwe …………………………………………………….. 14 NEWS ……………………………………………………………………………………… |  | | Journal (issue) | | Read, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - I. Knight, Scottish...paper. Teramae, Hirata and Soeda, colleagues of mine at Central Gem Laboratory, are thanked for their...Association tour: lab, gem collection • Steinkaulenberg mine tour • Historic and modern gem cutting workshop...wedgeshaped twinning (Figure 20) seen in synthetic quartz (Koivula and Fritsch, 1989). Synthetic spinel It..., 1989. The growth of Brazil-twinned synthetic quartz. Gems & Gemology, 25(3), 159-164 Koivula, J.I. |  | | Journal (issue) | | Nelson, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North East - N. R. Rose, North West...and comments on the exploration potential of the district. © Gemmological Association and Gem Testing Laboratory...Monte Bianco Domenico Pass Libiola Hill Gallinaria Mine (Casarza Ligure) Casa di Bonelli (Monte Tregin)...discovery of nephrite jade in the Sestri Levante district, controversy arose on the origin of the deposits...nephrite jade specimens from the Sestri Levante district is held in the Museum für Mineralogie und Geologie |  | Bristol, Samantha K., Spry, Paul G., Voudouris, Panagiotis Ch., Melfos, Vasilios, Mathur, Ryan D., Fornadel, Andrew P., Sakellaris, Gregory Aarne (2015) Geochemical and geochronological constraints on the formation of shear-zone hosted Cu–Au–Bi–Te mineralization in the Stanos area, Chalkidiki, northern Greece. Ore Geology Reviews, 66. 266-282 doi:10.1016/j.oregeorev.2014.11.001 | Journal (article/letter/editorial) | | Department of Mineralogy-Petrology, University of Athens, Athens 15784, Greece c Department of Mineralogy, Petrology...muscovite–biotite– chlorite–actinolite–feldspar–quartz schists of the Silurian Vertiskos Unit. Metallic...aggregates along foliation planes and in boudinaged quartz veins. Iron-bearing sulfides (pyrite, arsenopyrite...primary aqueous liquid–vapor inclusions in stage I quartz veins range from 170.1 °C to 349.6 °C (peak at...seawater contribution. For fluids in equilibrium with quartz, δ18O at 480 °C varies from 5.76 to 9.21‰ but does |  | | Journal (issue) | | Green, K. Gregory, J. Kalischer Branch Chairmen: Midlands – P. Phillips, North East – M. Houghton, North...sapphire and with the description of various synthetic quartz varieties. In contrast, the description of characteristic...sources, e.g. Russia, Brazil, Sri Lanka, Madagascar, Zimbabwe, India and Tanzania, are being compiled and, in...crystal had been found 15 years earlier in the Maxixe mine. This beryl had a deep blue colour, which faded...location of the Maxixe mine in Minas Gerais, Brazil, and state that the mine was closed when the loss |  | | Journal (issue) | | Shepherd, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - 1 . Knight, Scottish...and dolomite as the major constituents besides quartz (Figure 5). 65 Figure 3: A mined karstic channel...worn crystal faces or rounded surfaces and the quartz pebbles, which are also present occasionally in...wollastonite, wollastonite,calcite calciteand and quartz. quartz. These These minerals minerals show show polygonal...alexandrite from from the the Hematita Hematita mine mine in in Brazil Brazil (AL-HEMA1), (AL-HEMA1), an |
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