EDUCATION

• Gemological Institute of America (GIA), Graduate Gemologist program (GG)
  
  "I do not exaggerate when I say that my studies at GIA had the greatest impact on my professional gemmological career." Dr. Edward J. Gübelin, 1939
  
  The 6 month in-residence program at the Robert Mouawad Campus in Carlsbad, California is unparalleled for its laboratory practical requirement. One is exposed to a vast library of study stones brought up daily from the vault, as well as a course requirement of identification of thousands of laboratory specimens which increase in difficulty as the weeks proceed. It is an extremely demanding laboratory experience culminating with an "all or nothing" 20 stone exam as a final.
  
  The most recently published extensive written course materials (which are available for purchase to graduates with older editions) are beautifully presented, illustrated with gorgeous images and filled with concise information. After finishing the program, they become a permanent priceless addition to one's gemological reference library. I especially recommend the new colored stones lab manual as a worthwhile purchase. Though I am a student and devotee of the old lab manual, the new version is well worth its considerable weight.
  
  GIA's premier scientific journal Gems & Gemology, as well as its Loupe magazine, the Insider e-newsletter and continuing education and alumni programs offer some of the finest resources for continuing one's education.
  
  
• Gemmological Association of Great Britain (Gem-A), Fellow of the Gemmological Association (FGA) gemology program.
  
  The FGA program is the oldest, most rigorous and demanding in the field of gemology and has the most difficult final exams given. The stress is on theory and applying theory to practical application; every bit as difficult as my studies as a science major at Cornell University in the 1970's. Exams which are held twice yearly are comprised of the Foundation and Diploma. The final Diploma exam is 2 grueling days of detailed essay questions and a 25 stone practical requiring full descriptive work-ups for each stone. Of the 200 or so who sit the exams yearly worldwide, a little more than half qualify and of those, about a dozen do so with Merit...it is a very tough exam!.
  
  In order to be elected as a Fellow, one must not only pass the exams with a minimum grade of B, but also pay yearly dues in order to use the letters FGA after one's name. By having this membership requirement, one receives the bi-yearly peer-reviewed Journal of Gemmology and the bi-monthly Gems & Jewelery; publications which keep members current on scientific and technological issues.
  
  In the United States 151 gemologists currently hold the FGA; 8 of those also hold the DGA (2009). For the current register of FGA members worldwide, see the Gem-A online listing.

GEMS AND GEMOLOGY - REFERENCE BOOKS AND SUGGESTED READING:

Master Reference

•   Sinkankas, John. (1993) Gemology: An Annotated Bibliography. Scarecrow Press, Metuchen, N.J. (two volume set) 1216 pages.

  Journals  

• American Mineralogist
• Gems & Gemology (GIA)
  • International Gemological Symposium, Proceedings 1982
• Journal of Gemmology (Gem-A)
• Australian Gemmologist
• Canadian Gemmologist

Inclusions

• Hughes, R.W. (1990) A question of origin. Gemological Digest, Vol. 3, No. 1, pp. 16–32.(see Roedder below, same volume).
• Kim, Won-Sa (1996) Inclusions in Amethyst from Eonyang, Korea. Australian Gemmologist, Vol. XVII (1), pp.8-13.
• Kammerling, R.C. and Koivula, J.I. (1994) Microscopic features of synthetic rubies, part 1. Canadian Gemmologist, Vol. XV (3), pp.82-85.
• Kammerling, R.C. and Koivula, J.I. (1994) Microscopic features of synthetic rubies, part 2. Canadian Gemmologist, Vol. XV (4), pp.82-85.
•   Koivula, John I. (1989-present, series) A photolexicon of inclusion-related terms for today's gemmologist.
•   PhotoAtlas Series - If you order directly from the author through microWorld of Gems, the amount above his costs supports his research and ability to produce these books - instead of part of the profit going to a third party (and you can ask to have it signed by the author). This helps make it possible for microWorld of Gems to continue to bring us these wonderful resource books. They represent a huge body of work and background of unriveled expertise - I believe they are worth much more than than the asking price - most professional and research texts (medical and biological) that I have had to buy in the past have been more expensive. Please tell the Koivulas I sent you!
  
  
  •   Koivula, John I.(2000) The Microworld of Diamonds. Northbrook, IL: Gemworld International. 157 pages.
  •   Gübelin, Eduard J. and John I. Koivula. (2004) Photoatlas of Inclusions in Gemstones. 4th ed., Basel: Opinio Publishers, 532 pages.
  •   Gübelin, Eduard J. and John I Koivula. (2005) Photoatlas of Inclusions in Gemstones, Volume 2. Basel: Opinio Publishers. 829 pages.
  •   Gübelin, Eduard J. and John I Koivula. (2008) Photoatlas of Inclusions in Gemstones, Volume 3. Basel: Opinio Publishers. Orders are now being taken for this outstanding final volume which made its debut at the Gem-A Centenary Conference in October - it is a beautiful and quintessential book for one's personal gemological library.
    
    
• Roedder, E. (1962) Ancient fluids in crystals. Scientific American, 207, No. 4, 38-47
• Roedder, E. (1972) The composition of fluid inclusions. USGS Professional Paper 440, Chapter JJ, 12 plates, 164 pp.
• Roedder, E. (1981) Origin of fluid inclusions and changes that occur after trapping in L.S. Hollister and M.L. Crawford (editors), Fluid Inclusions: Applications to Petrology. Mineralogical Association of Canada Short Course Handbook, 6, 101-137.
•   Roedder, E. (1982) Fluid Inclusions in Gemstones: Valuable Defects. In International Gemological Symposium Proceedings 1982, ed. by D. M. Eash, Los Angles, GIA, pp. 479-502.
•   Roedder, E. (1984) Fluid Inclusions. Reviews in Mineralogy, vol. 12. Mineralogical Society of America, 644 pages. (an introduction to studies of all types of fluid inclusions, gas, liquid, or melt, trapped in materials from earth and space, and their application to the understanding of geologic processes).
• Roedder, E. (1985) Uses for synthetic fluid inclusions in quartz crystals. Nature, 315, 544-545.
• Roedder, E. and Belkin, H.E. (1988) Significance of monophase fluid inclusions in minerals. Comptes Rendus Acad. Sci. (Paris) (in English), 306, Ser. 2, 283-287.
• Roedder, E. (1990) Inclusions as criteria in gemstone origin reports. Gemological Digest, 3, no. 1, 24-26.
• Roedder, E. (1990) Fluid inclusion analysis -- Prologue and epilogue. Geochimica et Cosmochimca Acta, 54, 495-507.
•   Roedder, E. (1992) Optical Microscopy Identification of the Phases in Fluid Inclusions in Minerals. Microscope, Vol. 40, p. 59-79.
• Roedder, E. (2002) Fluid Inclusions, Encyclopedia of Physical Sciences and Technology, Third Edition, 2, 71-77.

Color

• Farrell, E.F. and Newnham, R.E. (1967) Electronic and vibrational absorbtion spectra in cordierite. American Mineralogist, Vol. 52, pp 380-388.
• Faye, G.H., Manning, P.G., and Nickel, E.H. (1968) The polarized optical absorbtion spectra of tourmaline, cordierite, chloritoid, and vivianite: ferrous-ferric electronic interaction as a source for pleochroism. American Mineralogist, Vol. 53, pp 1174.
•   Gems & Gemology series on origin of color in gem materials:
  • Frisch, Emmanuel and Rossman, George R. (1987) An update on color in gems. Part 1: Introduction and colors caused by dispersed metal ions. Gems & Gemology, Vol. 23, No. 3, pp. 126-139.
  • Frisch, Emmanuel and Rossman, George R. (1988) An update on color in gems. Part 2: Colors involving multiple atoms and color centers. Gems & Gemology, Vol. 24, No. 1, pp. 3-15.
  • Frisch, Emmanuel and Rossman, George R. (1988) An update on color in gems. Part 3: Colors caused by band gaps and physical phenomena. Gems & Gemology, Vol. 24, No. 2, pp. 81-101.
•   Nassau, Kurt. (1978) The Origins of Color in Minerals. American Mineralogist, Vol. 63 p. 219-229. (an excellent short course in causes of color in gem materials.)
•   Nassau, Kurt. (2001) The Physics and Chemistry of Color: The Fifteen Causes of Color. 2nd edition Wiley Interscience, Chichester. 481 pages.
•   Wise, Richard W. (2003) Secrets of the Gem Trade. Brunswick House Press 292 pages.( Learn the language of color. Richard has literally defined "connoisseurship," guiding the reader into the world of colored stone appreciation, enriching the journey with his passion for history and travel.)

Phenomenon

•   Gübelin, E.J. and Schmetzer, K. (1982) Gemstones with alexandrite effect. Gems & Gemology, Vol. 18, No. 4, pp 197-203.
•   Series by Asbjørn Halvorsen characterizing a color change phenomenon in Tanzanian chrome tourmaline christened the Usambara effect:
  • Halvorsen and Jensen, B.B. (1997) A new colour-change effect. Journal of Gemmology, Vol. 25, No. 5, pp. 325-330. (the first paper on Usambara effect. Letter from Dr. Kurt Nassau in following issue.)
  • Liu, Y. and Shigley, J.E. and Halvorsen. A. (1999) Colour hue change of a gem tourmaline from Umba Valley, Tanzania. Journal of Gemmology, Vol. 26, No. 6, pp. 386-396.
  •   Halvorsen, A. (2006) The Usambara effect and its interaction with other color-change phenomenon. Journal of Gemmology, Vol. 30, No. 1/2, pp. 1-21.
• Krzemnicki, M.S., Hänni, H.A. and Reusser, E. (2001) Colour-change garnets from Madagascar: comparison of colorimetric with chemical data. Journal of Gemmology, Vol. 27, 7, pp. 395-408.
• Kumaratilake, W.L.D.R.A.(1998) Spinel and garnet star networks: an interesting asterism in gems from Sri Lanka. Journal of Gemmology, Vol. 26, 1, pp. 24-28.
• Liu, Y. and Shigley, J.E. and Hemphill,S.(1995) Relationship between the crystallographic orientation and the "alexandrite effect" in synthetic alexandrite. Mineralogical Magazine, Vol. 59, pp. 111-114.
• Liu, Y. and Shigley, J.E., Fritsch,and E. Hemphill,S. (1999) A Colorimetric study of the alexandrite effect in gemstones. Journal of Gemmology, Vol. 26, No. 6, pp. 371-385.
• Liu, Y. and Shigley, J.E. (1999) Iridescence color of a shell of mollusk Pinctada margaritifera.Optics Express, Vol. 4, No. 5. pp. 177-182.
• Schmetzer, K. Kiefert, L. and Hänni, H.A. (1994) Asterism in beryl, aquamarine and emerald - an update. Journal of Gemmology, Vol. 29, 2, pp. 65-71.
• Schmetzer, K., Bernhardt, H.J.,and K. Kiefert, L. (2002) Star garnets and star garnet cat's eyes from Ambatondrazaka, Madagascar . Journal of Gemmology, Vol. 28, 1, pp.13-23.
• Schmetzer, K. and Glas, M. (2003) Multi-star quartzes from Sri Lanka. Journal of Gemmology, Vol. 28, 6, pp. 321-332.
• White, E.B., Rustrum, R. and Crichton, J.M. (1967) The "alexandrite effect:" an optical study. American Mineralogist, Vol. 52, pp 807-871.

Treatments and Synthetics

• Eeckhout, S.G, Sabioni, A.C.S., and Ferreira, A.C.M.(2004) A treatment study of Brazilian garnets. Journal of Gemmology, Vol. 29, 4, pp. 205-214.
• Karfunkel, J., Wegner, R.R.and Lobato, W. (1991) Some Fake "Gems" on the Brazilian market and how to identify them. Canadian Gemologist, Vol. XII, (1) pp 3-13.
•   Nassau, Kurt. (1980) Gems Made by Man. Radnor, PA: Chilton. 364 pages.
•   Nassau, Kurt. (1994) Gemstone Enhancement: History, Science and State of the Art. 2nd ed. London: Butterworth-Heinemann. 252 pages.
• Schmetzer, K. and Schupp, F.J. (1994) Dyed natural star corundum as a ruby imitation. Journal of Gemmology, Vol. 24, 4, pp. 253-255.
• Schmetzer, K. and Steinbach, M.P. (2002) Fake asterism - two examples. Journal of Gemmology, Vol. 28, 2, pp. 109-110.
• Schmetzer, K. (2002) Production of fake asterism. (letter to the editor) Journal of Gemmology, Vol. 28, 1, pp. 41-42.
• Schmetzer, K. and Glas, M. (2003) Treatments and techniques to create or enhance asterism in gemstones and imitations. Canadian Gemmologist, Vol. 24 (3), pp.82-93.
• Sun, Tay Thye (2005) Jade and its treatment. Canadian Gemmologist, Vol. 26 (4), pp.120-128.
•   Themelis, Ted. (1992) Heat Treatment of Ruby and Sapphire (out of print for now) Gemlab Inc., Thailand. 234 pages
•   Themelis, Ted. (2003) Beryllium-Treated Rubies and Sapphires. Gemlab Inc, Thailand. 48 pages.
•   Themelis, Ted. (2004) Flux-Enhanced Rubies and Sapphires. Gemlab Inc, Thailand. 50 pages.
• Themelis, Ted. (2005) Glass-filled rubies - clarity-enhanced rubies with glass-forming additives. Australian Gemmologist, Vol. 221, pp.360-365.

  extraLapis English  

• No.1 Madagascar - A Gemstone Paradise
• No.2 Emeralds of the World
• No.3 Tourmalines
• No.4 Calcite- The Mineral with the Most Forms
• No.5 Gold - The Noble Element
• No.6 Pakistan - Minerals, Mountains and Majesty
• No.7 Beryl and Its Color Varieties
• No.8 Elba - A Mineralogical Jewel in the Tuscan Archipelago
• No.9 Fluorite - The Collector's Choice
• No.10 Opal - The Phenomenal Gemstone
• No.11 Garnet- Great Balls of Fire!
• No.12 Bolivia - The Height of Mineral Collecting

Corundum

•   Hughes, Richard W. (1997) Ruby & Sapphire. RWH Publishing: Boulder, Colorado. 511 pages.
• Hughes, R.W. (1990) Corundum. London: Butterworth-Heinemann. 314 pages.
• Pisutha-Arnond, V., Häger, T., Atichat, W., and Wathanankul, P. (2006) The role of Be, Mg, Fe and Ti in causing colour in corundum. Journal of Gemmology, Vol. 30, 3/4, pp. 131-143.(my professors!)
• Saminpanya, Seriwat. (2001) Ti-Fe mineral inclusions in star sapphires from Thailand. Australian Gemmologist, Vol. 21, No. 3, pp. 125-128.(my professor!)
• Saminpanya, Seriwat, Manning, D.A.C., Droop, G.T.R., and Henderson, C.M.B. (2003) Trace elements in Thai gem corundums. Journal of Gemmology, Vol. 28, 7, pp. 399-415.

Feldspars

Garnets

• Adamo, I., Pavese, A., Prosperi, L., Diella, V., and Ajò, D. (2007) Gem-quality garnets: correlations between gemmological properties, chemical composition and infared spectroscopy. Journal of Gemmology, Vol. 30, 5/6, pp. 307-319.
• Akizuki, M.(1984) Origin of optical variations in grossular andradite garnet. American Mineralogist, Vol. 69, No. 3/4, pp. 328-338.
• Hainschwang, T. and Notari, F., (2006) The cause of iridescence in rainbow andradite from Nara, Japan. Gems & Gemology, Vol. 42, No. 4, pp 248-258.
• Hoover, D.B., Williams, C., Williams, B., and Mitchell, C. (2008) Magnetic susceptibility, a better approach to defining garnets. Journal of Gemmology, Vol. 31, 3/4, pp. 91-103.
•   Gems & Gemology series on Garnets:
  • Manson,V.D. and Stockton, C. M. (1981) Gem garnets in the red to violet color range. Gems & Gemology, Vol. 17, No. 4, pp 191-204.
  • Manson,V.D. and Stockton, C. M. (1982) Gem garnets in the orange to orange-red color range. In International Gemological Symposium Proceedings 1982, ed. by D. M. Eash, Los Angles, GIA, pp. 330-338.
  • Manson,V.D. and Stockton, C. M. (1982) Two Notable color-change garnets. Gems & Gemology, Vol. 18, No. 2, p.100-101.
  • Manson,V.D. and Stockton, C. M. (1982) Gem-quality grossular garnets. Gems & Gemology, Vol. 18, No. 4, pp 204-213.
  • Manson,V.D. and Stockton, C. M. (1983) Gem andradite garnets. Vol. Gems & Gemology, Vol. 19, No. 4, pp 202-208.
  • Manson,V.D. and Stockton, C. M. (1984) Pyrope-spessartine garnets with unusual color behavior. Gems & Gemology, Vol. 20, No. 4, pp 200-207. (defines color-shift)
  • Johnson, M.L., Boehm, E., Krupp, H., Zang, J.w., Kammerling, R.C. (1995) Gem-quality grossular andradite: a new garnet from Mali. Gems & Gemology, Vol. 31, No. 3, pp 152-166.
  • Schmetzer, K. and Bernhardt, H. J. (1999) Garnets from Madagascar with a color change of blue-green to purple. Gems & Gemology, Vol. 35, No. 4, pp 196-201. (blue garnets... at least in daylight)
  • Schmetzer, K., Hainschwang, T., Kiefert, L., and Bernhardt, H. J. (2001) Pink to Pinkish Orange Malaya Garnets from Bekily, Madagascar. Gems & Gemology, Vol. 37, No. 4, pp 296-308.
•   Pardieu, V. and Hughes, R.W.(2008) Tsavorite - the untamed beauty. InColor (Fall-Winter 2008-2009), pp 12-20. For the full story with additional photos and insights, see Dick Hughes'page http://www.ruby-sapphire.com/tsavorite-untamed-beauty.htm. Be sure not to miss the box at the end entitled "Tsavorite Geology" for an intriguing look into the connection between tsavorite and tanzanite - stay tuned for more about this in upcoming papers. You may also read the original InColor article and other very interesting gem related articles online at the ICA website: (requires RealRead) http://openpub.realread.com/rrserver/browser?title=/ICA_001/INCOLOR_WINTER2009
• Rossman, G. R. and Aines, R.D. (1986) Spectroscopy of a birefrigent grossular from Asbestos, Quebec, Canada. American Mineralogist, Vol. 71, pp 779-780.
•   Rouse, J. D.(1986) Garnet. Butterworth-Heinemann, London.

Pearls

• Gübelin, E.J.(1995) An attempt to explain the instigation of the formation of the natural pearl. Journal of Gemmology, Vol 24, No. 8, pp 539-545.
• Gutmannsbaruer, W. and Hänni, H.A. (1994) Structural and chemical investigations on shells and pearls of nacre forming salt and fresh-water bivalve mollusks. Journal of Gemmology, Vol 24, No. 8, pp 241-252.
• Landman, N.H. and Mikkelsen, P. (2001) Pearls, A Natural History. (American Museum of Natural History) Harry N. Abrams, N.Y. 232 pages.

• Strack, E. (2006)Pearls. Rühle-Diebener-Verlag. Stuttgart, Germany. 678 pages. (order through the publisher) Updated and expanded English translation of "Perlen" which was published in 2001."Pearls represents the most thorough, systematic update of knowledge about pearls since Kunz & Stevenson published their classic "The Book of the Pearls" in 1908. Congratulations to Elisabeth Strack for the dedication, research and scholarship that underpins this significant contribution to the gemmological literature." – Australian Gemmologist, Vol. 21 No. 6, April-June, 2002: Book review by Grahame Brown p.265

• Southgate, P.C. and Lucas, J.S., eds (2008) The Pearl Oyster. Elsevier Science & Technology Books, 544p. ( A comprehensive treatment of pearl oyster biology and pearl culture; making it an excellent companion to Strack's Pearls).

Quartz

• Bank, H. (1995) Amethysts and their occurances. Australian Gemmologist, Vol. 19, pp.175-177.
• Cohen, A.J. (1985) Amethyst color in quartz, the result of radiation protection involving iron. American Mineralogist, Vol. 70, pages 1180-1185.
• Garland, M.I. (2004) Amethyst in the Thunder Bay Region. Canadian Gemmologist, 25 (4), pp. 44-57.
• Güttler, R. S. and Kohigashi, H. C. (2006) Treated violetish blue to violet quartz from Brazil. Gems & Gemology, Vol. 42, No. 4, pp. 285-286.
• Hassan, F.A. and Cohen, A.J. (1974) Biaxial Color Centers in Amethyst Quartz. American Mineralogist, Vol. 59, pages 709-718.
• Henn, U. and Schultz-Guttler,R. (2009) Colour-enhanced quartz and its identification: green, violet-blue and yellow-green quartz from Brazil. Canadian Gemmologist, Vol. 30 no. 2, pp 46-54(Dr.Güttler on blue quartz).
• Kitawaki, H.(2006) Green quartz. http://www.gaaj-zenhokyo.co.jp/researchroom/kanbetu/2006/2006_05-01en.html, GAAJ Research Laboratory Report.
• Nassau, Kurt and Prescott, B. E. (1977) Smoky, blue, greenish yellow, and other irradiation-related colors in quartz. Mineralogical Magazine, Vol. 41, No. 319, pp 301-312.
• Nassau, Kurt and Prescott, B. E. (1977) A unique green quartz. American Mineralogist, Vol. 62, pp 589-590.
• Nunes, E.H.E. and Lamereiras, F.S. (2005) The optical abstorption of gamma irradiated and heat treated natural quartz. Materials Research, Vol. 8. No. 3. pp. 305-308.
Chichester. 481 pages.
• Paradise T.R. (1982) The Natural Formation and Occurrence of Green quartz. Gems & Gemology, Vol. 18, No. 1, pp. 39-42.
• Schmetzer, K. (1989) Methods for the distinction of natural and synthetic citrine and prasiolite. Journal of Gemmology, Vol 21, No. 7. pp 368-391.
• Zolensky, ME, Sylvester, P.J. and Paces, J.B. (1988) Origin and significance of blue coloration in quartz from Llano rhyolite (llanite), north-central Llano County, Texas. American Mineralogist, Vol. 73, No. 3/4 p. 313-325.

Diamonds

•   Pagel-Theisen, Verena. (2001) Diamond Grading ABC: the Manual. 9th ed. Antwerp, Belgium: Rubin & Son. 320
pages.
•   Roskin, Gary A. (1994) Photo Masters for Diamond Grading. Northbrook, IL: Gemworld International. 99 pages.
• The GIA Diamond Dictionary. (1993) 3rd ed. Santa Monica, CA: Gemological Institute of America. 275 pages.
• Harlow, George E. (1997) The Nature of Diamonds.Cambridge University Press. 288 pages.
•   Kraus, E.H. and Slawson, C.B. (1939) Variation of Hardness in the Diamond. American Mineralogist, Vol. 24, pp 661-676.
• Peters, Nizam. (1998) Rough Diamonds, Internal and External Features .American Institute of Diamond Cutting. 47 pages
• Peters, Nizam. (1999) Rough Diamonds, A Practical Guide. American Institute of Diamond Cutting. 170 pages

Spectroscopy

•   Winter, Colin H. (2003)A Students Guide to Spectroscopy. Leatherhead, Surrey: OPL Press. 85 pages.
•   Anderson, Basil W., and James Payne. (1998) The Spectroscope and Gemmology. Woodstock, VT: GemStone Press. 269 pages.

Techniques and Other Instrumentation

• Crowningshield, G.R. and Ellison, J.G. (1951) The determination of important opitcal properties without instruments. Gems & Gemology, Vol. 7, No. 4, pp 120-124.
•   Hanneman, W.W. (1980) Educating the eyeball - the Hodgkinson Method. Lapidary Journal, Vol. 34, 7, pp. 1498-1519.
• Hanneman, W.W. (1982) Understanding the Hodgkinson Method. Journal of Gemmology, Vol. 18, 3, pp. 221-228.
• Hanneman, W.W. (2000) The Hanneman Refractometer. Journal of Gemmology, Vol. 27, 3, pp. 155-160.
•   Hanneman, W.W.(2001) Guide to Affordable Gemology. 2nd Ed. Hanneman Gemological Products. Poulsbo, WA.
• Hodgkinson, Alan. (1979) Visual Optics. Journal of Gemmology, Vol. 17, 5, pp. 301-309.
• Hodgkinson, Alan. (1992) Simple advanced refractometer technique: determining optic sign. Canadian Gemmologist, XIII (4), pp. 114-117.
• Hodgkinson, Alan. (1994) Visual optics - the Hodgkinson method - an update. Canadian Gemmologist, XV (2), pp. 50-54.
• Hodgkinson, Alan. (1995) The Hanneman-Hodgkinson Sythetic Emerald Filter. Canadian Gemmologist, XVI (1), pp. 18-22.
•   Hodgkinson, Alan.(1995) Visual Optics. Gemworld International, Inc. Northbrook, Illinois. 50 pages (with 1996 update).
• Hodgkinson, Alan. (1998) The spread of visual optics. Canadian Gemmologist, XIX (3), pp. 74-78.
• Hodgkinson, Alan. (1998) Gemstones in a new light. Australian Gemmologist, Vol. 20, pp. 246-249.
• Hodgkinson, Alan. (2006) Test case for the refractometer - olivine or sinhalite? Australian Gemmologist, Vol. 22, pp. 493-495.
• Hodgkinson, Alan.(2008) A useful refractometer method. Canadian Gemmologist, 29 (1), pp. 12-22.
• Hoover, D.B. (2003) A critical review of the Hanneman refractometer. Journal of Gemmology, Vol. 28, 6, pp. 353-361.
• Hoover, D.B.and Williams, Bear (2005) Crossed filters revisited. Journal of Gemmology, Vol. 29, 7/8, pp. 473-481.
•   Hoover, D.B.and Williams, C. (2007) Better refractometer results with bright line technique. Journal of Gemmology, Vol. 30, 5/6, pp. 287-2961. (see follow-up letter to editor from Alan Hodgkinson where he gives examples.)
• Hurlbut, C.S. (1984) The jeweler's refractometer as a mineralogical tool. American Mineralogist, Vol. 69, pp. 391-398.
•   Linton, Trevor (1995) The hazardous effects of refractometer contact fluid. Australian Gemmologist, Vol. 19, p. 185.(1.79 vs 1.81, also in J. of Gemm.)
• Linton, Trevor (1999) Refractometers and the pin-hole disc (at close range). Australian Gemmologist, Vol. 20, pp. 227-229.
• Linton, Trevor (1999) Evaluation of a teaching aid for 'Visual Optics." Australian Gemmologist, Vol. 20, pp. 232-235.
• Linton, Trevor, Cumming, A., and Hunter, K. (2003) Large OPL diffraction grating spectroscope. Australian Gemmologist, Vol. 21, pp. 410-412.
• Linton, Trevor (2005) Practical application for measuring gemstone dispersion on the refractometer. Australian Gemmologist, Vol. 22, pp. 330-344.
• Linton, Trevor. (2006) Re-surfacing a refractometer prism- what are the consequences? Can it be done effectively? Australian Gemmologist, Vol. 22, pp. 470-471.
• Gumpesberger,S. (2003) Pocket LED light sources for gemmologists (part 1). Canadian Gemmologist, 24 (3), pp. 94-101.
• Gumpesberger,S. (2003) Pocket LED light sources for gemmologists (part 2). Canadian Gemmologist, 24 (4), pp. 119-126.
• Gumpesberger, S. (2006) Magnetic separation of Gemstones. Canadian Gemmologist, 27 (4), pp. 121-124.
•   Kammerling, R.C.and Koivula, J.I. (1989) Beware of anomalous instrument reactions. Canadian Gemmologist, XI (3), pp. 82-87.
•   Kammerling, R.C.and Koivula, J.I. (1990) Gem instruments: an owner's guide to care and maintenance. Canadian Gemmologist, X (4), pp. 102-107.
• Song, X., Wu, R., and Wu, W. (2005) The variation of RI with rotation of doubly refractive gemstone on the refractometer hemicylinder. Journal of Gemmology, Vol. 29, 5/6, pp. 331-340.
• Lamarre, C. (2002) Light emitting diodes as light sources in portable gemmological instruments. Journal of Gemmology, Vol. 28, 3, pp. 169-174.
• Sturman, Darko and Back, M.E. (2002) Doubling of images in gemstones. Journal of Gemmology, Vol. 28, 4, pp. 210-222.
•   Sturman, Darko. (2005) Use of the polarizing filter on the refractometer. Journal of Gemmology, Vol. 29, 5/6, pp. 341-348. (download the chart as a pdf file).
• Sturman, Darko. (2005) Use and misuse of optical mineralogy constants in gemmology. Australian Gemmologist, Vol. 22, pp. 234-243. (with corrections to text)
• Sturman, Darko. (2007) Identification of gemstones using a graph based on birefringence and maximum refractive index. Canadian Gemmologist, 28 (2), pp. 55-59.
• Sturman, Darko. (2007) Determination of the optic axial angle in biaxial gemstones and its use in gemmology. Journal of Gemmology, Vol. 30, 7/8, pp. 443-452.
• Sturman, Darko. (2007) Clarification of measurement of the RIs of biaxial gemstones on the refractometer. Journal of Gemmology, Vol. 30, 7/8, pp. 434-442.
• Williams, Bear (2008) Magnetism in gem testing. Gem Market News, Vol. 27 (3), pp. 7-8,13.

Un-filed

• Hlaing, U Tin (1999) Burmite - Burmese Amber. Australian Gemmologist, Vol. 20, pp.250-253.
•   Kristjansson, L. (2002) Iceland Spar: The Helgustadir calcite locality and its influence on the development of science. Journal of Geoscience, Vol 50, No. 4, pp 419-427. Dr. Kristjansson's paper (pdf file, 559 KB reproduced with permission of the author). A more recent and vastly updated paper in Icelandic will be available soon in English.
•   Scovil, Jeff. Photographing Minerals, Fossils and Lapidary Materials. a href="http://www.scovilphoto.com/
• Saminpanya, Seriwat, Sutherland, F.L. (2008) Black Opaque Gem Minerals Associated with Corundum in the Alluvial Deposits of Thailand. Australian Gemmologist, Vol. 23, No. 6, pp. 242-253.
• Sersen, W.J. (1989) Buying and selling gems: what light is best? Part 1: Natural Light. Gemological Digest, Vol 2, No. 4, pp. 13-23.
• Sersen, W.J. (1990) Buying and selling gems: what light is best? Part 2: Artificial light - the options available. Gemological Digest, Vol 3, No. 1, pp. 45-56.
• Sturman, Darko and Back, M.E. (2002) Doubling of images in gemstones. Journal of Gemmology, Vol. 28, 4, pp. 210-222.
• Sinkankas, John.(1984) Gem Cutting, A Lapidary's Manual, 3rd Ed. Chapman and Hall, NYC. 365 pages.
• Sinkankas, J., (1988) Sinkankas Standard Catalog of Gem Values. Geoscience Press, Prescott, Arizona.
• Stevens, E. L., (1999) The Nomenclature of gemstones with special reference to the garnet and tourmaline mineral groups. Australian Gemmologist, Vol. 20, pp. 277-279.
• Vargas, G. and Vargas, M. (1989) Faceting for Amateurs, 3rd ed. Published by the authors,Thermal, California. 340 pages.

INTERNET

• FMF Mineral Forum: http://www.mineral-forum.com/message-board/
• Mineralogy Society of America: http://www.minsocam.org/
• Dr. George Rossman of CalTech - including lists of publications dealing with color and properties of gem minerals http://www.gps.caltech.edu/%7Egrr/index.html
• Dr. Brad Amos: http://homepage.ntlworld.com/w.amos2/Brad%20Amos's%20Website/page4.html
• AGTA GTC News Archive: http://www.agta.org/gtc/news.html
• GIA: http://www.gia.edu/3954/gia_home_page.cfm
• Gem-A: http://www.gem-a.info/
• Scottish Branch of the Gemmological Association: http://www.scotgem.co.uk/
• Gemmological Association of All Japan Research Lab reports: http://www.gaaj-zenhokyo.co.jp/index-e.html
• GIT Lab Updates: http://www.git.or.th/eng/eng_index.htm
• SSEF: http://www.ssef.ch/
• Gübelin Gem Lab: http://www.gubelinlab.com/
• LMHC Information Sheets on the Gübelin Gem Lab site: http://www.gubelinlab.com/lmhc.asp
• AIGS inclusion image library: http://www.aigsthailand.com/Inclusion_Pictures.aspx
• The Guide: Gem Market News excerpts: http://www.gemguide.com/news.htm
• Stone Group Labs: http://www.stonegrouplabs.com/
• GRS: http://www.gemresearch.ch/
• Ted Themelis http://themelis.com/
• Mineralogy Database: http://webmineral.com/index.shtml
• Mindat.org: http://www.mindat.org/index.php
• Mike and Darcy Howard - Crystal Systems: http://www.rockhounds.com/rockshop/xtal/index.html
• Friends of Jade: http://www.friendsofjade.org/
•   Emerald Case Time Line - Fred Ward http://www.ganoksin.com/borisat/nenam/emerald-case-intro.htm
• The Quartz Page: http://www.quartzpage.de/index.html
• Brain Press, the Best from Charles Lewton-Brain: http://brainpress.com/index.html.