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2023 AGA Tucson Conference - February 1, 2023

2023 AGA Tucson Conference and Gala...
with the Bonanno Award Presentation to Gary Roskin

Wednesday, February 1, 2023 at the Tucson Marriott University Park

2023 AGA Tucson Conference

8:00 a.m. Registration opens with coffee and light refreshments.
8:30 a.m. – 4:30 p.m. Conferenece

2023 AGA Tucson Gala

6:30 p.m. Cocktails
7:00 p.m. - 11:00 p.m. Dinner, Silent Auction, Dancing, & Bonanno Award Presentation

About speakers and topics...

Direct Registration links:

Early registration savings for the In-Person Conference is available until December 31, 2022

*All conference gemological presentations will be live-streamed, recorded, and made available to Virtual and In-Person registrants when made published by AGA.

In-person attendees will receive optional participation in the hands-on sessions, interaction with our vendor tables at conference breaks, lunch and light refreshments, a ticket to the evening Gala, and a full-day (and evening) of networking amongst some of the world’s leading gemologists.

Meg Berry

Meg Berry

Meg Berry has been a lapidary artist working in the gem and jewelry industry since 1974. She studied gem cutting at Grieger's Inc. in Pasadena, California, where she was awarded a Master Faceter Certificate. She also studied gemology at the Gemological Institute of America (GIA) and received designations in Colored Stones and Gem Identification. Working at Grieger’s and later a large Los Angeles wholesale gem house, in 1989, she joined Pala International, Inc. as a full-time cutter faceting myriad of fine and rare colored stones, as well as cabbing, carving, and repairing and re-cutting damaged stones. Currently, Meg owns and operates Megagem, where she works as a lapidary for the trade and accepts commissions of custom cutting for private clients.

Highly recognized for her skill as a lapidary and gemstone carver, Meg has been awarded more than a dozen American Gem Trade Associations' (AGTA) Spectrum - Cutting Edge awards. In 1992, the late treasure hunter, Mel Fisher, commissioned Meg to facet the largest of the rough emerald crystals recovered from the Spanish galleon "Atocha," which sank in 1622 in the Florida straits. Her works is also appreciated daily by all at GIA World headquarters, as during the construction of the GIA campus in Carlsbad, California, the late Vince Manson commissioned Meg to cut and polish the concept pieces of rocks and slabs placed as name plates outside each door.

Meg currently produces one-of-a-kind extraordinary gemstone creations using a combination of techniques that may include faceting, carving, frosting, and piercing—sometimes all on the same stone! Her work is thematic, designed to elicit an emotional response and an appreciation for the beauty of Nature.

Mark Cullinan

Mark Cullinan, Owner and CEO of Cullinan Diamonds

Mark was born and grew up in South Africa and is the great grandson of Sir Thomas Cullinan who discovered the Premier (now Cullinan) Diamond mine where the Cullinan Diamond was discovered in 1905.

Mark obtained a business degree at the University of Cape Town and after achieving an MA in Politics and Economics at Oxford University, where he was a cricket Blue and played first class cricket, he qualified as a member of the Society of Investment Analysts and worked for 10 years in investment in the City of London. He has been involved in the diamond industry for the past 30 years from when he was on the board of a family JSE listed royalty company that had an interest in the Venetia diamond mine in South Africa.

He has a Diamond Grading diploma and Rough Diamond diploma from the HRD in Antwerp and was involved in diamond prospecting activities in South Africa over a period of 10 years. He wrote an article on prospecting for diamonds which  can be found in the 2019 edition of the Journal of the Gemmological Association of Hong Kong.

Mark is owner and CEO of Cullinan Diamonds a company dealing in diamonds, investment diamonds and jewellery and which holds the intellectual property for Cullinan Diamonds. In conjunction with Dr. Thomas Hainschwang of the GGTL Laboratory Liechtenstein, the laboratory produces the "Cullinan Diamond Report" which provides an unique 'fingerprint' identification of a diamond.

Alan Hodgkinson

“Live Stream interview with Alan Hodgkinson”

Streaming live from Scotland, Alan Hodgkinson will join the 2023 AGA Conference for an informal interview and discussion of his legendary gemological career.

Alan Hodgkinson began his career in the jewelry industry in 1957 and earnt his FGA with distinction in 1961, before becoming the first Group Training Officer for the Jewelry Trade in 1969. He set up own business as a manufacturing jeweler in 1973 which enabled him to gradually build a collection of specimens for teaching gemology.

Since those early days, Alan's abilities and reputation have gone from strength to strength. Among his many career milestones are:

Alan has written many well-received articles for gemology journals as well as authoring his own book, Gem Testing Techniques, first published in 2015. After selling out its first run, Gem Testing Techniques was reprinted in 2021.

Robert Weldon

Robert Weldon

Digital Photography of Gemstones and Jewelry

A practical, eye-opening "how-to" that focuses on the photography tools, gem staging and positioning, lighting approaches - as well as some post-processing techniques of gemstone and jewelry photography.

Robert Weldon is director of GIA's Richard T. Liddicoat Library in Carlsbad, California, leading a team of librarians and subject matter experts. He is positioning the library to not only be a critical archive for researchers and students, but also a significant digitized content producer for the Institute.

He pursues writing assignments at gem localities and often leads gem photography projects in those global locations. Weldon has visited gem sites in Myanmar, India, East Africa and southern Africa, Colombia, Bolivia, Brazil, Russia, and other sources. He speaks Spanish and German fluently and is a well-known public speaker on gemological subjects. Robert is the recipient of the 2020 Antonio C. Bonanno Award for Excellence in Gemology. He has reported extensively on gemological issues for over three decades. He was a senior editor at JCK, and later Professional Jeweler magazines before returning to GIA in 2006.

Weldon's photography is published in international gemological, jewelry, and consumer publications and in several books, including Splendour & Science of Pearls, which he co-authored and edited. A Rough Guide for Artisanal Miners is an educational booklet which he has also lectured on and delivered to artisanal miners in Tanzania and other East African countries. His photographs have appeared on more than 35 covers of GIA's scholarly publication, Gems & Gemology, where he has published a number of peer-reviewed articles on subjects such as the Museum of London's Cheapside Hoard, Botswana's diamond industry, Colombia's Chivor emerald mine, the gemstones of the Taj Mahal and the Mughals, and the extraordinary carvings from the Dreher family of Idar-Oberstein, Germany.

Gary Roskin

Gary Roskin

New Directions for the International Gem Trade Show Business

A look at how global economics alter the gem exhibitions landscape. What we have learned over the past two years about how to operate an on-line business, and how to work successfully from home, affects in-person trade shows. Trade shows aren’t just another fun place where you can go visit gem dealers. They are a business. And they know that if they cannot attract the in-person exhibitor or buyer, they too must pivot.

Gary Roskin, gemologist, author, gemstone photographer, and journalist, is the Editor in Chief of the Roskin Gem News Report.

Former CEO for the International Colored Gemstone Association, Senior Gemstone Editor for JCK Magazine, and the Baselworld Daily News, Roskin has covered the international-colored gems and diamonds market, as well as gemological subjects on diamonds, and the estate gemstone/jewelry market for close to four decades.

With years of professional experience in areas including laboratory diamond grading, supervising, training, monitoring, and reporting, Roskin has provided jewelers and appraisers valuable diamond grading tips and techniques. Gary is the author of Photo Masters for Diamond Grading.

Roskin began his career as a fourth-generation retail jeweler in Marion, Indiana. He studied at the Gemological Institute of America (GIA) in Santa Monica, California, and worked there from 1977 through 1992; 6 years as Assistant to the Director of the Los Angeles GIA Gem Trade Lab, 3 years as a resident gemology instructor in both diamond grading and colored stone/gem identification, and 5 years as Executive Director of the GIA Alumni Association. From 1992 through 1997, Roskin was Assistant Director for the European Gem Lab in Los Angeles.

Roskin is a Graduate Gemologist and Fellow of the Gemmological Association of Great Britain. Gary has been the recipient of many awards, including the International Society of Appraiser's Media Award for his feature story entitled, Bad Appraising Lands Good Jeweler in Court, several Richard T. Liddicoat Journalism Awards Honorable Mentions from the American Gem Society, and a shared 2nd place award in Gems & Gemology's Dr. Edward J. Gübelin Most Valuable Article Award, as a co-author of Synthetic Gem Materials in the 2000s: A Decade in Review.
Dr. Clemens Schwarzinger

Dr. Clemens Schwarzinger

Tanzanite and fancy zoisites - color, chemistry and cutting

Tanzanite, the blue variety of the mineral zoisite, is, despite being known only for about 60 years, among the most coveted gemstones of our time. But zoisite is also found in a range of other colors and it does even have three different colors along each crystallographic axis, a phenomenon known as trichroism. We have analyzed hundreds of samples in terms of chemistry and how trace elements influence the color and why some materials can be heat-treated to improve their color while others will suffer from this treatment. And finally, we will have a look at this material through the eyes of a gem cutter – how orientation, positioning of color zones and design of special cutting patterns can help to create unique gems.

Dr. Clemens Schwarzinger is associate Professor for chemistry at the Johannes Kepler University Linz, Austria. In 2016 he founded the Center for Scientific Gemmology at the University Linz and is scientific advisor of the Viennese Diamond Bourse. He is owner of a small company which is dedicated to precision gemstone cutting and developing novel cutting designs. In 2017 he won the US Faceters Guild Single Stone competition in the Master category, in 2018 and 2019 he was certified as Grand Master. In 2021 he was winner of the Gem A Photo Competition.

His academic research interests (in terms of gemmology) focus on the identification of gem treatments and mineral chemistry, particularly on the use of trace elements for origin determination of garnets and coloration of zoisite/tanzanite as well as advanced spectroscopy. He is also lifelong collector of minerals with an emphasis on gem species.

Dr. Schwarzinger is widely published and holds professional memberships in: Austrian Gemmological Society (ÖGemG), Austrian Chemical Society (GÖCH), American Society of Mass Spectrometry (ASMS), and Gemmological Society of Great Britain (Gem A).

Sarah  Caldwell Steele

Hands-on Workshops (1-3)

Session 1, by Sarah Caldwell Steele

Back to Black

Black stone identification is acknowledged to be one of the most challenging areas of C21st gemology. Traditional gemological testing techniques rely heavily on information coming from the stone’s interior and the transmission of light through the stone, but of course, in the case of black, opaque materials, observers are limited to surface or near surface features to aid identification. When we consider the black natural and semi-synthetic biopolymers, usually termed 'organics' the problem is intensified since they are often collectively termed 'jet' despite in reality comprising of some 40+ species. This practical session will familiarize you with the different species and varieties encountered in jewelry and give the basic skills necessary to differentiate between them.

Sarah Caldwell Steele has had a love affair with Whitby jet since the age of seven. Reinforcing 40 years of commercial experience of working jet as a lapidary product, she graduated from Durham with a Degree in Geology in 1992. She was awarded Fellowship of the Gemmological Association of Great Britain in 2013, and subsequently Diamond Fellowship in 2015. Her gemmological prowess lies in the identification of black gem materials including natural and semi-synthetic biopolymers. Sarah is widely considered the world's leading authority on the jet species of gemstones and is a regular speaker on the subject at national and international conferences. Her work to establish a new nomenclature system for gem-quality hydrocarbons and ultimately determine country of origin for jet is challenging previous perceptions of these ancient and culturally important gem materials.

In 2019 she returned to Durham University as a PhD candidate. Her project aims to establish a new methodology for the identification of jet artefacts in the archaeological record, drawing on her own practitioner experience and those techniques employed by the contemporary indigenous lapidary practitioners of Europe, Asia and the Americas.

Richard Hughes

Session 2, by Richard Hughes

Jade Identification

This workshop will focus on the identification of jade (nephrite and jadeite), including simulants and treated jade.

Richard W. Hughes is one of the world's foremost experts on ruby and sapphire. The author of several books and over 170 articles, his writings and photographs have appeared in a diverse range of publications, and he has received numerous industry awards. Co-winner of the 2004 Edward J. Gübelin Most Valuable Article Award from Gems & Gemology magazine, the following year he was awarded a Richard T. Liddicoat Journalism Award from the American Gem Society. In 2010, he received the Antonio C. Bonanno Award for Excellence in Gemology from the Accredited Gemologists Association. The Association Française de Gemmologie (AFG) in 2013 named Richard as one of the fifty most important figures that have shaped the history of gems since antiquity. In 2016, Richard was awarded a visiting professorship at Shanghai's Tongji University. 2017 saw the publication of Richard and his wife and daughter's Ruby & Sapphire • A Gemologist's Guide, arguably the most complete book ever published on a single gem species and the culmination of nearly four decades of work in gemology. In 2018, Richard was named Photographer of the Year by the Gem-A, recognizing his photo of a jade-trading market in China, while in 2020, he was elected to the board of directors of the Accredited Gemologists Association and was appointed to the editorial review board of Gems & Gemology and The Australian Gemmologist magazine. Richard's latest book, Jade • A Gemologist's Guide, was published in 2022.

Kerry Gregory

Session 3, by Kerry Gregory

Treasure from Trash – Hands-On!

Learn how to quickly, efficiently, and profitably sort through a mixed parcel of gemstones to find the value. Using her decades of experience in this field, Kerry will show you how to quickly spot then screen gems, using a polariscope, to find the stuff that will make you money!

Kerry Gregory FGA DGA, founder of Gemmology Rocks, National Association of Jewellers' (UK) Service Provider of the year, is a professional gemmologist and jewellery industry specialist. She has worked in the industry for over 20 years in a variety of fields, working, studying and honing her craft. She started Gemmology Rocks to deliver real life development and practical vocational education to businesses; getting to the root of frustrations and problems and providing solutions and education to tackle the stuff that make a difference every day in business, and makes more money. Anyone who has met Kerry, knows she is a one-woman hirlwind, passionate, funny and motivating, she is described in many ways by people, but never described as boring! Kerry's talk, if previous talks are anything to go by, will be a fast paced, entertaining and educational experience.


Generous financial support from these organizations helps us deliver the superior year-round level of education and participant experience our attendees have come to expect from AGA.

We encourage AGA members and supporters to consider our sponsors for your professional needs.

2023 AGA Sponsorships available - contact Teri Brossmer


Scottish Gemmological

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