The Mineralogy and Geochemistry of the Green Giant Vanadium-Graphite Deposit, S.W
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The Mineralogy and Geochemistry of the Green Giant Vanadium-Graphite Deposit, S.W. Madagascar by Veronica Di Cecco A thesis submitted in conformity with the requirements for the degree of Masters of Applied Science Department of Geology University of Toronto © Copyright by Veronica Di Cecco 2013 The Mineralogy and Geochemistry of the Green Giant Vanadium-Graphite Deposit, S.W. Madagascar Veronica Di Cecco Masters of Applied Science Department of Geology University of Toronto 2013 Abstract The purpose of this project was to determine the vanadium bearing ore minerals present at the Green Giant vanadium-graphite deposit in the S.W. of Madagascar owned by Toronto based Energizer Resources Inc. The rocks are mainly quartzofeldspathic gneiss, with alternating bands of hornblende biotite gneiss, marble, granitoid, and amphibolite. Using X-ray diffraction, electron microprobe analysis, and Raman spectroscopy, the vanadium bearing minerals were identified as vanadium bearing rutile, schreyerite, berdesinskiite, karelianite, a member of the karelianite-eskolaite solid solution, V-bearing phlogopite, V-bearing pyrrhotite, V-bearing pyrite, goldmanite, dravite, uvite, actinolite, and unidentified “V-sulphide 1,” “V-sulphide 2,” “V- silicate 1.” The mineral assemblage present at Green Giant deposit is quite similar to that at Lake Baikal, Russia. Vanadium-bearing phlogopite is primary vanadium host in the deposit, although V-bearing oxides contribute substantially to the total V concentration, even where present in very trace amounts. ii Acknowledgments Thank you to Professors E.T.C Spooner and K. Tait for your assistance and guidance. Thanks to Brendt Hyde, Vincent Vertolli, Katherine Dunnell and Tony Steede at the Royal Ontario Museum Department of Natural History, Mineralogy section, Professor Mike Gorton, Colin Bray, George Kretchman, Allison Enright, Christopher White and Beata Opalinska at the University of Toronto Department of Earth Sciences, and Craig Scherba at Energizer Resources Inc. Last but not least, many thanks to Adam Duyvestyn and my family for their continued support. iii Table of Contents Acknowledgments.......................................................................................................................... iii Table of Contents ........................................................................................................................... iv List of Tables ................................................................................................................................ vii List of Figures ................................................................................................................................ ix List of Common Symbols and Abbreviations ............................................................................... xii List of Appendices .........................................................................................................................xv Chapter 1 Introduction .....................................................................................................................1 1 Vanadium ....................................................................................................................................1 1.1 Geological Associations.......................................................................................................2 Chapter 2 Madagascar......................................................................................................................4 2 Geography ...................................................................................................................................4 2.1 Geology ................................................................................................................................5 Chapter 3 The Green Giant Vanadium and Graphite Property ........................................................8 3 Property Geology ........................................................................................................................8 Chapter 4 Vanadium Host Minerals ..............................................................................................11 4 Introduction ...............................................................................................................................11 5 Methods .....................................................................................................................................11 5.1 Field Visit and Sampling ...................................................................................................11 5.2 Material for Study ..............................................................................................................12 5.3 Examination of Material ....................................................................................................13 6 Results .......................................................................................................................................15 6.1 XRD and Hand Sample Identification ...............................................................................15 iv 6.2 X-Ray mapping ..................................................................................................................17 6.3 Electron Microprobe Analysis ...........................................................................................19 7 Mineral Species .........................................................................................................................20 7.1 V-Bearing Oxides ..............................................................................................................20 7.1.1 Ti-Oxide: Vanadium Bearing Rutile ......................................................................20 7.1.2 V-Ti-oxide 1: “Schreyerite” ...................................................................................23 7.1.3 V-Ti-Oxide 2: “Berdesinskiite” .............................................................................28 7.1.4 V-Cr-Oxide: a member of the karelianite – eskolaite solid solution .....................33 7.1.5 V-oxide: “Karelianite” ...........................................................................................36 7.2 V-Bearing Sulphides ..........................................................................................................38 7.2.1 V-sulphide 1: Unknown .........................................................................................38 7.2.2 V-Sulphide 2: Unknown ........................................................................................40 7.2.3 Fe-V-Sulphide 1: V-bearing Pyrrhotite .................................................................42 7.2.4 Fe-V-Sulphide 2: Vanadium bearing pyrite ...........................................................43 7.3 V-silicates ..........................................................................................................................44 7.3.1 V-silicate 1: Unknown ...........................................................................................44 7.3.2 V-Silicate 2: V-phlogopite .....................................................................................45 7.4 Summary table ...................................................................................................................48 7.5 Comparison to Lake Baikal, Russia ...................................................................................50 Chapter 5 Vanadium Reconciliation ..............................................................................................52 8 Methods .....................................................................................................................................52 9 Results .......................................................................................................................................52 10 Discussion .................................................................................................................................53 Chapter 6 Conclusion .....................................................................................................................55 References ......................................................................................................................................56 v Appendix I Vanadium Concentrations as Provided by Energizer Resources Inc. .........................61 Appendix II Mineral Identifications Performed at the Royal Ontario Museum ...........................63 Appendix III V-Rutile EMPA Data ..............................................................................................72 Appendix IV Schreyerite EMPA Data ..........................................................................................73 Appendix V Berdesinskiite EMPA Data ......................................................................................74 Appendix VI Karelianite-Eskolaite SS EMPA Data ....................................................................75 Appendix VII V-Phlogopite EMPA Data .....................................................................................76 Appendix VIII The Results of X-Ray Fluorescence Performed at the University of Toronto on the Working Set of Samples .................................................................................................79 vi List of Tables Table 1: Tectonic events recorded in the tectonic units of Madagascar, from Collins (2006) ....... 6 Table 2: A list of the number of samples which comprise