Diamond Treatments
High-Pressure, High-Temperature (HPHT) Diamond Processing: What Is this Technology and How Does It Affect Color?
Sonny Pope
Natural Diamond Enhancement: The Transformation of Intrinsic and Impurity Defects in the Diamond Lattice
Victor G. Vins, Alexander P. Yeliseyev, Sergei V. Chigrin, and Alex G. Grizenko
Gem Characterization Techniques
The Gemstones of the Shrine of the Three Magi (ca. 1200 AD) in CologneCathedral, Germany
Manfred Burianek
Defects in Single-Crystal CVD Synthetic Diamond Studied by Optical Spectroscopy with the Application of Uniaxial Stress
David Charles, Alan T. Collins, Gordon Davies, and Philip Martineau
Overview of Dislocation Networks in Natural Type IIa Diamonds
Katrien De Corte, Ans Anthonis, Jef Van Royen, Maxime Blanchaert, Julien Barjon, and Bert Willems
Luminescence, Reflected-Infrared, and Reflected-Ultraviolet Digital Photography: Gemological Applications
Shane Elen and Sheryl Elen
Magnetic Separation of Gemstones
Sylvia M. Gumpesberger
A Variation on the Crossed Filters Approach Using Pocket LED Light Sources
Sylvia M. Gumpesberger
Cathodoluminescence Spectroscopy to Identify Types of Natural Diamond
Hisao Kanda
The Identification of Gemstones by Photoluminescence: Synthetic and Natural Mg-Al Spinels
Leonardo Maini, David Ajò, and Sylvana Ehrman
Fingerprinting Gem Beryl Samples Using Laser-Induced Breakdown Spectroscopy (LIBS) and Portable X-ray Fluorescence (PXRF)
Nancy J. McMillan, Catherine E. McManus, Tori L. Gomez, Russell S. Harmon, Frank C. De Lucia Jr., and Andrzej W. Miziolek
Color Grading of Color-Enhanced Natural Diamonds: A Case Study of Imperial Red Diamonds
Sergei Smirnov, Sergei Ananyev, Victoria Kalinina, Victor Vins, and Alex Grizenko
Study of the Biaxial Gemstones on the Refractometer
Darko B. Sturman
Inclusions in White-Gray Diamonds of Cubic Habit from Siberia
Sergey V. Titkov, Yulia P. Solodova, Anatoliy I. Gorshkov, Larisa O. Magazina, Anatoliy V. Sivtsov, Elena A. Sedova, Murad D. Gasanov, and Georgiy G. Samosorov
General Gemology
Ruby-Sapphire Quality Grading for the Gem Trade
Wilawan Atichat, Pongchan Chandayot, Visut Pisutha-Arnond, Pornsawat Wathanakul, Sakda Siripant, Sakrapee Saejoo, Chotima Kunwisutpan, Boontawee Sriprasert, and Chakkaphant Sutthirat
Coated Topaz
Riccardo Befi, Lore Kiefert, and Min Htut
Three-Dimensional Solid Modeling in Applied Diamond Crystallography
Mike Botha, Courtenay Keenan, and Robert Ward
Characterization of Sapphires from Yogo, Montana
Andrea Cade, Branko Deljanin, Lee Groat, and Marina Epelboym
Statistical Study of the Performance and Predictive Value of Color Measurement Instruments for Cape-Colored Rough Diamonds
Tom Ceulemans and Eva Van Looveren
“Bahia Gold” Golden Rutilated Quartz, Serra da Mangabeira, Novo Horizonte, Bahia, Brazil
Brian Cook
Software for Gemstone Grading and Appraisal Valuation
Richard B. Drucker
Demantoid from Iran
Garry Du Toit, Wendi Mayerson, Carolyn van der Bogert, Makhmout Douman, Riccardo Befi, John I. Koivula, and Lore Kiefert
Fluorescence of Fancy-Color Natural Diamonds
Sally Eaton-Magaña, Jeffrey E. Post, Roy A. Walters, Peter J. Heaney, and James E. Butler
The Bragança “Diamond” Discovered?
Rui Galopim de Carvalho
The Evolution of the American Round Brilliant Diamond (aka American Cut), 1860–1955
Al Gilbertson
Funding for Gemological Research: Ideas and Case Studies
Lee A. Groat
Relationship between Texture and Crystallization Degree in Nephrite Jade from Hetian, Xinjiang, China
Mingyue He
Integrating the Diamond Project Development Process
Karin O. Hoal
Melo “Pearls” from Myanmar
Han Htun, William Larson, and Jo Ellen Cole
Global Rough Diamond Production from 1870 to 2005
A. J. A. (Bram) Janse
Identification of Beryl Varieties: “Beryl Color Circle,” “Color Memory,” and a Proposed New Variety—Chromaquamarine
Arunas Kleismantas
Gemological Properties of Colorless Hyalophane from Busovaca, Bosnia-Herzegovina
Goran Kniewald and Vladimir Bermanec
Some Dissolution Features Observed in Natural Diamonds
Taijin Lu, Mary L. Johnson, and James E. Shigley
The Role of Brillianteering Variations in the GIA Cut Grading System
Ilene Reinitz, Al Gilbertson, and Ronnie Geurts
Preliminary Observations of a New Polishing Process for Colored Gems
Peter Richardson, Tom Stout, Carley McGee-Boehm, William Larson, and Edward Boehm
Identification of Dyed Chrysocolla Chalcedony
Andy Shen, Eric Fritz, Dino DeGhionno, and Shane McClure
Study of Interdependence: Fancy-Color Diamond Appearance, Cut, and Lighting Conditions
Sergey Sivovolenko and Yuri Shelementiev
Comparative Investigation of Diamonds from Various Pipes in the Malaya-Botuobiya and Daldyn-Alakit Areas (Siberia)
Yulia P. Solodova, Elena A. Sedova, Georgiy G. Samosorov, and Konstantin K. Kurbatov
The “Keshi” Pearl Issue
Nick Sturman and Ali Al-Attawi
A System to Describe the Face-up Color Appearance of White and Off-white Polished Diamonds
Thomas E. Tashey Jr. and Myriam C. Tashey
Digital Color Communication for Gemstones, with an Exploration of Applications within Our Industry
Thom Underwood, Menahem Sevdermish, and Liat Sevdermish
Photographing Phenomenal Gemstones
Robert Weldon
Recent Trends in World Gem Production
Thomas R. Yager
Geology of Gem Deposits
The Importance of Surface Features and Adhering Material in Deciphering the Geologic History of Alluvial Sapphires—An Example from Western Montana
Richard B. Berg and Christopher F. Cooney
Mining of Pegmatite-related Primary Gem Deposits
Jim Clanin
What Determines the Morphology of a Resorbed Diamond?
Yana Fedortchouk and Dante Canil
Jadeite Jade from Guatemala: Distinctions among Multiple Deposits
George E. Harlow, Sorena S. Sorensen, Virginia B. Sisson, and John Cleary
Mineral Assemblages and the Origin of Ruby in the Mogok Stone Tract, Myanmar
George E. Harlow, Ayla Pamukcu, Saw Naung U, and U Kyaw Thu
Major Diamond Mines of the World: Tectonic Location, Production, and Value
A.J.A. (Bram) Janse
Geology of Placer Gem Deposits
James M. Prudden
Three Parageneses of Ruby and Pink Sapphire Discovered at Fiskenæsset, Greenland
William Rohtert and Meghan Ritchie
Controls on Mineralization in Block D´ of the Merelani Tanzanite Deposit, Tanzania
Reyno Scheepers
Texture and Composition of Kosmochlor and Chromian Jadeite Aggregates from Myanmar: Implications for the Formation of Green Jadeite
Guang-Hai Shi, Bernhard Stöckhert, and Wen-Yuan Cui
Pegmatite Genesis—Complex or Simple Emplacement? Revisiting Southern CaliforniaPegmatites
Lawrence W. Snee, Eugene E. Foord, Douglas M. Morton, Gary P. Landis, Robert O. Rye, and J. Blue Sheppard
Geology of “True” Hiddenite Deposits
Michael A. Wise
Laboratory Growth of Gem Materials
Optical Characterization of CVD Synthetic Diamond Plates Grown at LIMHP-CNRS, France
Ans Anthonis, Olivier De Gryse, Katrien De Corte, Filip De Weerdt, Alexandre Tallaire, and Jocelyn Achard
New Data for Distinguishing between Hydrothermal Synthetic, Flux Synthetic, and Natural Corundum
Alexei S. Bidny, Olga S. Dolgova, Ivan A. Baksheev, and Irina A. Ekimenkova
Study of Fancy-Color and Near-Colorless HPHT-grown Synthetic Diamonds from Advanced Optical Technology Co., Canada
Branko Deljanin, Dusan Simic, Marina Epelboym, and Alexander M. Zaitsev
A Refined Infrared-Based Criterion for Successfully Separating Natural from Synthetic Amethyst
Stefanos Karampelas, Emmanuel Fritsch, Triantafyllia Zorba, Konstantinos M. Paraskevopoulos, and Spyros Sklavounos
New Gem Localities
Ultraviolet Mineral Prospecting for Sapphire on Baffin Island, Nunavut, Canada
Luc Lepage and William Rohtert
Gemological Investigation of Multicolored Tourmalines from New Localities in Madagascar
Margherita Superchi, Federico Pezzotta, and Elena Gambini
