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Microscopic, Chemical and Spectroscopic Investigations on Emeralds of Various Origins

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Microscopic, Chemical and Spectroscopic Investigations on Emeralds of Various Origins Microscopic, chemical and spectroscopic investigations on emeralds of various origins Dissertation zur Erlangung des Grades „Doktor der Naturwissenschaften“ am Fachbereich Chemie, Pharmazie und Geowissenschaften der Johannes Gutenberg-Universität Mainz Le Thi Thu Huong geb. in Thanh Hoa, Vietnam Mainz, 2008 Dekan: 1. Berichterstatter: 2. Berichterstatter: Tag der mündlichen Prüfung: Hereby I declare that I have written the present doctoral thesis on my own and without any illegal help. All literature sources are indicated. Mainz, April 2008 --------------------------- Contents CONTENTS CONTENTS ------------------------------------------------------------------------------------------------------------------------i INDEX OF FIGURES------------------------------------------------------------------------------------------------------------ iii INDEX OF TABLES------------------------------------------------------------------------------------------------------------- vii ABBREVIATIONS --------------------------------------------------------------------------------------------------------------viii ACKNOWLEDGEMENT ------------------------------------------------------------------------------------------------------ ix ABSTRACT ------------------------------------------------------------------------------------------------------------------------x ZUSAMMENFASSUNG-------------------------------------------------------------------------------------------------------- xi 1. INTRODUCTION AND OBJECTIVES ----------------------------------------------------------------------------------- 1 1.1. THE CRYSTAL STRUCTURE OF BERYL -------------------------------------------------------------------------- 1 1.2. POSSIBILITIES TO DETERMINE ORIGINS OF EMERALDS AND SEPARATION BETWEEN NATURAL EMERALDS FROM SYNTHETIC ONES – STATE OF THE ART STUDY AND RESULTS OF THE PRESENT THESIS------------------------------------------------------------------------------------------------------------------------ 4 2. SHORT DESCRIPTION OF SAMPLES AND ORIGINS------------------------------------------------------------- 10 2.1. NATURAL EMERALDS ------------------------------------------------------------------------------------------ 10 Colombia --------------------------------------------------------------------------------------------------------- 10 Brazil ---------------------------------------------------------------------------------------------------------------- 11 Austria ------------------------------------------------------------------------------------------------------------- 14 Russia --------------------------------------------------------------------------------------------------------------- 15 Zambia ------------------------------------------------------------------------------------------------------------ 16 South Africa ------------------------------------------------------------------------------------------------------ 16 China -------------------------------------------------------------------------------------------------------------- 16 Nigeria ------------------------------------------------------------------------------------------------------------- 17 Madagascar ---------------------------------------------------------------------------------------------------- 17 Classification of the emerald deposits ----------------------------------------------------------------- 18 2.2. SYNTHETIC EMERALDS ----------------------------------------------------------------------------------------- 18 2.2.1. Flux-grown synthesis ---------------------------------------------------------------------------------- 19 2.2.2. Hydrothermally-grown synthesis ------------------------------------------------------------------ 20 3. INCLUSIONS -------------------------------------------------------------------------------------------------------------- 22 3.1. Chivor (Colombia) -------------------------------------------------------------------------------------------- 22 3.2. Santa Terezinha (Brazil) -------------------------------------------------------------------------------------- 25 3.3. Socoto (Brazil) --------------------------------------------------------------------------------------------------- 27 3.4. Carnaiba (Barzil) ----------------------------------------------------------------------------------------------- 30 3.5. Capoeirana (Brazil) ------------------------------------------------------------------------------------------- 31 3.6. Itabira (Brazil) ---------------------------------------------------------------------------------------------------- 32 3.7. Manajary (Madagascar) ----------------------------------------------------------------------------------- 34 3.8. Habachtal (Austria) ------------------------------------------------------------------------------------------- 37 3.9. Kafubu (Zambia) ----------------------------------------------------------------------------------------------- 38 3.10. Gwantu (Nigeria) -------------------------------------------------------------------------------------------- 40 3.11. Transvaal (South Africa) ----------------------------------------------------------------------------------- 41 3.12. Ural (Russia) ---------------------------------------------------------------------------------------------------- 42 3.13. Malipo (China) ------------------------------------------------------------------------------------------------ 44 3.14. Flux-grown syntheses ---------------------------------------------------------------------------------------- 45 3.15. Hydrothermally-grown syntheses ----------------------------------------------------------------------- 47 Discussion -------------------------------------------------------------------------------------------------------------- 48 i Contents 4. CHEMICAL PROPERTIES OF INVESTIGATED EMERALDS ----------------------------------------------------- 52 4.1. Silicon (Si) -------------------------------------------------------------------------------------------------------- 54 4.2. Aluminium (Al) ------------------------------------------------------------------------------------------------- 55 4.3. Beryllium (Be) --------------------------------------------------------------------------------------------------- 55 4.4. Lithium (Li) ------------------------------------------------------------------------------------------------------- 56 4.5. Sodium (Na) ---------------------------------------------------------------------------------------------------- 57 4.6. Magnesium ((Mg) --------------------------------------------------------------------------------------------- 58 4.7. Gallium (Ga) ---------------------------------------------------------------------------------------------------- 58 4.8. Caesium (Cs) --------------------------------------------------------------------------------------------------- 58 4.9. Iron (Fe) ----------------------------------------------------------------------------------------------------------- 59 4.10. Niobium (Nb) and Strontium (Sr) ----------------------------------------------------------------------- 59 4.11. Titanium (Ti) ---------------------------------------------------------------------------------------------------- 60 4.12. Nickel (Ni) ------------------------------------------------------------------------------------------------------ 60 4.13. Rubidium (Rb) ------------------------------------------------------------------------------------------------ 60 4.14. Vanadium (V) ------------------------------------------------------------------------------------------------ 61 4.15. Molybdenum (Mo) ------------------------------------------------------------------------------------------ 61 4.16. Potassium (K) -------------------------------------------------------------------------------------------------- 62 4.17. Manganese (Mn) -------------------------------------------------------------------------------------------- 62 4.18. Chromium (Cr) ----------------------------------------------------------------------------------------------- 63 4.19. Scandium (Sc) ------------------------------------------------------------------------------------------------ 63 Discussion -------------------------------------------------------------------------------------------------------------- 64 5. RAMAN MICRO-SPECTROSCOPY OF EMERALDS ------------------------------------------------------------- 67 5.1. Raman spectra in the range from 200 cm-1 to 1600 cm-1 -------------------------------------- 68 5.1.1. Comparisons of Raman spectra up to 1600 cm-1 of emeralds from various deposits ---------------------------------------------------------------------------------------------------------- 69 5.1.2. Bands around 1067-1072 cm-1 ------------------------------------------------------------------- 73 5.2. Raman spectra of emeralds at high Raman shift: 3500-3700 cm-1 -------------------------- 77 5.2.1. Measurements under room temperature --------------------------------------------------- 77 5.2.2. Measurements under low temperatures ----------------------------------------------------- 80 6. INFRARED SPECTROSCOPY OF EMERALDS --------------------------------------------------------------------- 86 6.1. IR absorption spectroscopy in the range 400-1500 cm-1 --------------------------------------- 89 6.2. IR absorption spectroscopy in the ranges 1500-1700 cm-1 and 3300-3800 cm-1 -------- 98 CONCLUSIONS -------------------------------------------------------------------------------------------------------------- 102 REFERENCES ---------------------------------------------------------------------------------------------
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