Gemstone fashioning Lapidary techniques. Cutting styles. Diamond cuts: a retrospect. Setting styles.

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1 GEMOLOGY GEOL 3140 Syllabus and Guidelines Objectives The primary objectives of this course are to teach you the principles of gemstone identification, appraisal and certification. Other topics covered in the course include the history of gemology, occurrence of gemstones in nature, gemstone enhancement techniques, and synthetic gem materials. The course includes a comprehensive lab component that will give you an opportunity to acquire some basic hands-on experience in gem identification using gemological instruments (refractometer, dichroscope, etc.). Instructor Dr. Anton Chakhmouradian (Department of Geological Sciences, 230 Wallace Building, phone , address CHAKHMOU@cc.umanitoba.ca) Availability for questions/comments: Tuesdays & Thursdays, 3:00-5:00 pm. Feel free to ask questions during or after lectures and labs. Lecture outline (Mon, Wed & Fri; 10:30-11:20 am) Introduction to the course What is a gemstone? Classification of gemstones. Gemology in retrospect. The importance of instrumental methods for gem identification. Famous gemologists and reputable gem collections. Gemological institutes and professional associations. Gem trade and associated professional organizations. Gemstone fashioning Lapidary techniques. Cutting styles. Diamond cuts: a retrospect. Setting styles. Diagnostic properties of gem materials (These lectures focus on the specifics of gemstone identification; for basics on physical and optical properties of minerals, please refer to your lecture notes and texts for GEOL 2500, GEOL 2540 and GEOL 2600) Hardness. Tenacity, cleavage and fracture. Specific gravity and density. Theory of color vision. The nature of color in gemstones. Luster. Optical effects (iridescence, adularescence, play of color, opalescence, aventurine effect, chatoyancy, asterism). Color change and pleochroism. Optical spectra. Transmission, reflection and refraction. Critical angle. Index of refraction. Prism refractometer. High-RI refractometers. Polarization of light. Optical axiality, sign and orientation. Luminescence, fluorescence and phosphorescence. Instrumental methods in gemology Optical stereo microscope and illumination techniques. Filters. Prism, diffraction-grating and digital-scanning spectroscopy. Spectrophotometers. Dichroscope. Photoluminescence tests. Critical-angle and other refractometers. Immersion technique. Polariscope. Thermal conductivity measurements and diamond testers. More advanced testing techniques (X-ray diffraction and micro-diffraction, photoluminescence, etc.) and the problem of prohibitive analytical cost. Cutting-edge analytical techniques (Raman spectroscopy, mass-spectrometry) and their application in gemological research. Inclusions and other inhomogeneities in gemstones Inclusions in inorganic gem materials (pre-existing, syngenetic and epigenetic) and their significance. Growth features and zoning. Deformation features. Twinning. Inclusions in amber. 1

2 Gemstone enhancement Dyeing and color backing. Coating. Composite (assembled) stones. Oiling and impregnation. Heat treatment. Surface diffusion. Irradiation. Inclusion removal. Fracture and cavity filling. Bleaching. What enhancement practices are legitimate? Rules of disclosure. Naturally occurring gemstones and their deposits (This series of lectures will focus on individual types of gemstones. They will be discussed in the order: name and formula > deposits > history of use > characteristic properties > distinction from similar stones. Please note that many gemstone names do not comply with the internationally approved classification of minerals. For instance, even though sapphire and ruby represent the same mineral, they are considered in the gemological literature as two distinct gemstones. For the complete list of gemstones covered in this course, see next page). Synthetic gem materials and imitations Synthetic gemstones and imitations (simulants). History of gemstone synthesis. Diamond synthesis. Verneuil method. Czochralski method. Flux-assisted growth. Floating-zone method. Hydrothermal synthesis. Skull-crucible method. Man-made gem materials with no natural analogues: CZ, YAG, GGG, YIG, lithium niobate, etc. Popular gemstone simulants. How to distinguish imitations and man-made gems from the real thing? A brief history of gemstone use and abuse Gems as cultural heritage. Famous diamonds, rubies, sapphires and emeralds. Famous lapidary works. Trends and fashions in jewelry of the past and present. Gems as energizers and healers? Gem and diamond trade. Conflict diamonds. The history of Canadian diamonds. Labs (Fri 2:30-4:30) The labs are intended to introduce you to the principal methods of gemstone identification, and then test your knowledge and practical skills. You will be trained to use the instruments that constitute the essential arsenal of any gemologist, including the stereoscopic microscope, refractometer, polariscope, dichroscope, spectroscope, Chelsea filter and testers. The training will include work with a representative collection of natural and synthetic gem materials. You will also gain some hands-on experience in using gemological software and printed reference materials. Evaluation procedures* Midterm test (lecture material, March 7) 20% Final exam (lecture material, TBA) 40% Written assignment and presentation in class 15% (presentation and (including literature research, one page essay and minute paper valued equally) presentation on the topic of your choice, to be discussed in the first lab) In-lab test 1 (identification of phenomenal gemstones) 5% In-lab assignment 1 (color characteristics of gemstones) 9% In-lab assignment 2 (characterization and identification of cut gemstones) 11% * To pass this course, you must earn a passing score on both of its components (theory and lab). You are referred to the University of Manitoba Undergraduate Calendar for the University policies on plagiarism, cheating and impersonation at examinations. For further information, see 2

3 Please note that the deadline for voluntary withdrawal is March 18, Books There are many good texts on various topics of gemology and even on individual types of gemstones. Below, I list only those that are comparatively affordable or available in the Science & technology Library and may assist you in this course. required text Gemmology, 2 nd edition, by Peter G. Read (1999), Butterworth- Heinemann, Oxford additional literature (1) Practical Gemmology Robert Webster / Published: 1999 / Published by Antique Collectors' Club (2) Gems: Their Sources, Descriptions and Identification Robert Webster, Peter G. Read / Published: 1994 / Published by Butterworth-Heinemann (3) Gem Testing Anderson Jobbins, Alan Jobbins / Published: 1990 / Published by Butterworth-Heinemann (4) The Nature of Diamonds George Harlow (ed.) / Published: 1998 / Published by Cambridge University Press (5) Opals Fred & Charlotte Ward / Published: 2000 / Published by Gem Book Publishers (6) Diamonds Fred & Charlotte Ward / Published: 1998 / Published by Gem Book Publishers (7) Emeralds Fred & Charlotte Ward / Published: 1996 / Published by Gem Book Publishers (8) Rubies and Sapphires Fred & Charlotte Ward / Published: 1995 / Published by Gem Book Publishers (9) Jade Fred & Charlotte Ward / Published: 1995 / Published by Gem Book Publishers (10) Pearls Fred & Charlotte Ward / Published: 1995 / Published by Gem Book Publishers (11) Quartz Michael O Donoghue / Published: 1987 / Published by Butterworth-Heinemann (12) Man-made Gemstones Dennis Elwell / Published: 1979 / Published by John Wiley & Sons (13) Dictionary of Gems and Gemology Robert M. Shipley / Published: 1974 / Published by GIA (14) Gemstones: Symbols of beauty and power Eduard J. Gübelin, F.-Z. Erni / Published: 2000 / Published by Gem Guides Book Co. (15) Gemstones Mary Lou Dean / Published: 1991 / Published by Vantage Press (16) Gemstones of the World Walter Schumann / Published: 2000 / Published by Sterling Publications (17) The Encyclopedia of Minerals and Gemstones Michael O Donoghue / Published: 1980 / Published by Galahad Books (18) Simon & Schuster's Guide to Gems and Precious Stones Kennie Lyman (editor) / Published: 1986 / Published by Distican, Inc (19) Standard Catalog of Gem Values Anna M. Miller, John Sinkankas / Published: 1994 / Published by Geoscience Press, Incorporated (20) Gemstones Christine Woodward / Published: 1988 / Published by Sterling Publications (21) DK Handbooks: Gemstones Cally Hall et al. / Published: 1994 / Published by DK Publishing (22) Encyclopedia of Rocks, Minerals and Gemstones Henry Russell, Chris Pellant / Published: 2001 / Published by Thunder Bay Press 3

4 Journals Gems and Gemology News on gemstones, synthetic materials, trends in gemstone and jewelry markets; contents of the back issues available on-line; annual subscription (4 issues) available from (recent issues can be loaned from the X-ray Crystallography library) Journal of Gemmology coverage similar to the Gems and Gemology, annual subscription (4 issues) available from (recent issues can be loaned from the Mineral Synthesis library) Lapidary Journal - Gem, jewelry and bead magazine; contents of the back issues available on-line; annual subscription (12 issues) available from Useful Internet resources Professional societies/associations Canadian Gemmological Association (CGA) - International Colored Gemstone Association (ICA) - Gemological Institute of America (GIA) - Swiss Gemmological Institute (SSEF) - Gemmological Association of Great Britain (Gem-A) - The Gemmological Association of Australia - Prominent museum collections/exhibitions: American Museum of Natural History, New York - (virtual tours of gemstone exhibitions, access via Search) Smithsonian Institution, Washington (DC) - (virtual tour; access via Collections) Miscellaneous links: Colored Stone - (links to gem-related products and gem dealers; gem show guides; news and classifieds) Tradeshop Inc. - (comprehensive gemstone library with images; pages on gemstone enhancement, care, etc.) The Opalmine - (a lot of information on Australian opals) Ruby & Sapphire - (the name speaks for itself) All About Jewels - (illustrated dictionary) A.M.W. Gems - (gemstone library) Gem Collectors Forum - (gemstone library with images) 4

5 Complete list of gemstones covered in the course (including group and varietal names) Achroite Garnet Padparadscha Verdelite Actinolite Goshenite Paraìba tourmaline Vesuvianite Agate Pearl Alexandrite Hawk s-eye Pectolite Zircon Albite Heliodore Peridot Zoisite Almandine Heliotrope Prasiolite Amazonite Hematite Pyrope Amber Hessonite Pyrophyllite Amethyst Hiddenite Ametrine Quartz Ammolite Idocrase Andalusite Imperial topaz Rhodolite Andradite Imperial jade Rhodochrosite Anorthite Indicolite Rhodonite Apatite Iolite Rose quartz Aragonite Ivory Rubellite Aquamarine Ruby Aventurine Jade Jadeite Sapphire Balas ruby Jasper Sard Beryl Jet Sardonyx Bixbite Serpentine Blister pearl Kunzite Scapolite Burmese jade Schorl Labradorite Shell (mollusc) Cairngorm Larimar Smoky quartz Calcite Lapis lazuli Sodalite Cat s-eye Lazurite Spectrolite Chalcedony Leucosapphire Spessartine Charoite Liddicoatite Sphalerite Chinese jade Sphene Chrome diopside Mabé pearl Spinel Chrome tourmaline Malachite Spodumene Chrysoberyl Malaia garnet Star ruby Chrysoprase Mali garnet Star sapphire Citrine Maxixe beryl Steatite (soapstone) Copal Microcline Sugilite Coral Moldavite Sunstone Cordierite Moonstone Corundum Morganite Tanzanite Moss agate Thulite Demantoid Tiger s-eye Diamond Nephrite Titanite Diopside Topaz Dravite Obsidian Topazolite Odontolite Tourmaline Elbaite Onyx Transvaal jade Emerald Onyx marble Tsavorite Opal Turquoise Feldspar Orthoclase Fluorite Uvarovite Forsterite Umbalite 5

6 Most Common Gemstones MINERALOGICAL NAME Actinolite Albite Almandine Andalusite Andradite Anorthite Aragonite Beryl Calcite Charoite Chrysoberyl Cordierite Corundum Diamond Diopside Elbaite Forsterite Grossular Hematite Hydoxylapatite Jadeite Lazurite Malachite Microcline Opal Pectolite Pyrope Quartz Rhodochrosite Rhodonite Sodalite Spessartine Spinel Spodumene Topaz Turquoise Vesuvianite Zircon Zoisite NAME(S) USED BY GEMOLOGISTS & IN THE GEM TRADE one specific variety: nephrite (Chinese jade) usually iridescent: moonstone local names are common usually Cr-bearing green: demantoid iridescent: spectrolite; aventurescent: sunstone in pearls, marble onyx varietal names: emerald, aquamarine, morganite, etc. in marble onyx, coral + varieties: alexandrite, cymophane iolite, dichroite varietal names: ruby, sapphire, star ruby, etc. ; varietal names used for phenomenal diamonds (green transmitter, chameleon diamond, etc.) varietal names: tashmarine, chrome-diopside varietal names: rubellite, Paraíba, verdelite, etc. peridot varietal names: rhodolite, Mali garnet, etc. in ivory, odontolite principal constituent of Burmese jade principal constituent of lapis lazuli aventurescent: sunstone varietal names: black opal, fire opal, etc. one specific variety: larimar + varieties: (rhodolite, malaya, etc.) local names are common (e.g., Elie ruby) varietal names: amethyst, citrine, agate, etc. (with a color-specific modifier) varietal names: kunzite, hiddenite varietal names (including treated varieties): imperial, London blue, etc. transparent: idocrase; massive translucent: californite varietal names: tanzanite, thulite 6

7 List of Potential Topics for Term Paper No. Title (1) Vibrational spectroscopy: an introduction (2) Mass spectrometry and its role in gemological research (3) Vibrational spectroscopy and the study of diamonds (4) Tracking the provenance of gemstones using spectroscopy and massspectrometry (5) Tracking the provenance of gemstones using inclusions (6) Fancy colored diamonds: notable examples and grading principles (7) Pearls: origin, characteristics and classification (8) Pearl farming and pearl grading (9) Chrysoberyl and alexandrite (10) Jade (11) Opal (12) Lapis lazuli: more than meets the eye (13) Phenomenal gemstones (other than pearls, opal, star corundum and alexandrite) (14) Gemstone deposits in pegmatites: an overview (15) Gemstone deposits in regional-metamorphic rocks: an overview (except emerald, jade, ruby and sapphire) (16) Gemstone deposits in volcanic rocks: an overview (except diamond and sapphire) (17) Historical diamonds of India and South Africa (18) Recent gemstone discoveries ( s) (compile a list and check with Instructor) (19) Ethics issues related to gemstone mining and trade (20) Gemstone exploration and mining in Canada (except diamond) 7

Gem-A Diploma in Gemmology Course Specifications (2009 ed)

Gem-A Diploma in Gemmology Course Specifications (2009 ed) Contents page Introduction 2 Assessment objectives 2 Scheme of assessment 2 Diploma syllabus 5 Constants of syllabus stones 7 Further information