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2017 AGA Tucson Conference, Wednesday, Feb. 1, 2018 held at the Tucson University Park Hotel.

What you missed:

Cutting Edge Gemology to keep you in the loupe

What's Important for the Gemstone Industry in 2017?

Gary Roskin, Executive Director of the International Colored Stone Association (ICA)

Chris Smith

Relevant to appraisers and dealers alike, this session by Gary Roskin provided his insights and perspective of what is important for the gemstone industry in 2017. Roskin has been a key guest in previous AGA conferences as a chronicler of the gem industry and with his newest position heading ICA, brings world-wide access to the most current trends, pricing and regulations.

"This session was a great compliment to that of Chris Smith from American Gemological Laboratories," explains AGA President Stuart Robertson. "Chris presented a new concept to the nomenclature of color gem descriptions. His research and recommendations are currently being tested and reviewed by the world's major laboratories leading this exclusive unveiling at the AGA conference."

In Search of Consistency: Color Terms in Gemology and the AGL Approach

Christopher Smith, American Gemological Laboratory (bio)

... an exclusive unveiling at the AGA conference!

The "Art" of the Gem Deal

Art Samuels, GG (GIA) (bio)

Art Samuels revealed how he uses "The System" to find and buy gems, improve them, obtain lab reports, then mount and market them. He shared his views on misunderstood basics of lighting used in evaluating and grading gems, lab reports, pricing, synthetic and treated diamonds, appraising, and hot current issues that fit into his one hour time restriction. Art is a practical gemologist who is also very opinionated and outspoken. His presentation will be informative and certainly not dull.

Art Samuels is an extremely qualified gemologist, an astute businessman, a skilled treasure hunter and a captivating speaker. His unique background includes 24 years of active Naval service and 29 years as the owner of several successful wholesale and retail gem and jewelry businesses in South Florida. Art is active in many trade organizations and on boards including on our own AGA Board. He uses his compelling verbal and writing skills as a consumer advocate, a champion of change, and a positive force to improve Gemological practices and ethics.

From Gemology to Mineral Physics & Back Again

Included an update on a gem of the future: Nano-Polycrystalline Diamond

Elise Skalwold, Consulting Gemological Curator, Cornell University (bio)

In the author's ever-expanding experience of the world of gems, the study of gemology has led her on an unexpected and fascinating journey into the realms of mineralogy and high-level mineral physics research. Through a behind-the-scenes tour of her own collaborative research projects, this presentation gave the audience a taste of the complex scientific efforts which directly or indirectly support the day-to-day gemological science on which the gem industry relies, but which often remain relatively invisible. Central to the story are her co-researchers and other colleagues who enrich the quest for understanding and interpreting this fascinating world.

The thread which binds this journey is the intense investigation of a blue crystal included within a diamond macle. Over a four year period, some of the most technologically advanced instrumentation in the world has yielded volumes of data and a conclusion that this pleochroic crystal is olivine, though as yet no conclusive reason for its anomalous color. Nonetheless, the high degree of scrutiny to which this diamond and its inclusions have been subjected is in itself a remarkable story and provides insights into a world deep within the Earth – arguably one of its last frontiers and one which is otherwise inaccessible.

Inextricably linked to this story is the Diamond Anvil Cell (DAC), a remarkable instrument used in high pressure research. Not only does the DAC utilize gem quality diamonds in its own construction, it is also used to study the Deep Earth environment in which diamonds form. Gemmy nano-polycrystalline diamond (NPD) plays an important role in both the DAC and in our understanding of natural gem diamonds.

Elise A. Skalwold is an AGA Accredited Senior Gemologist, independent researcher, educator and author. She serves as Consulting Gemological Curator at her alma mater, Cornell University (B.Sc. 1982), and is Contributing Editor and author for the quarterly column G&G Micro-World featured in Gems & Gemology, the peer-reviewed scientific journal of the Gemological Institute of America (GIA). READ MORE…

Secrets of the Hope Diamond Revealed

Recent research projects update a storied history

Dr. Jeffery Post, Curator, Gem and Mineral Collection, Smithsonian Institution (bio)

The Hope Diamond is one of the most famous gemstones in the world. It is familiar to most people because of its fascinating human history which includes kings and thieves and perhaps a curse or two, but it is also a rare blue diamond, the largest and finest of its kind known. Despite its long history in the public eye, the diamond still prompts many questions.

Was the Hope Diamond cut from the great French Blue Diamond that was stolen during the French Revolution in 1792? Are there other blue diamonds that were cut from the same original parent stone as the Hope Diamond? Why does the Hope Diamond emit an intense ember-orange glow after exposure to ultraviolet light? This illustrated presentation explored the history of the Hope Diamond and described recent research projects that attempted to unlock some of the secrets of the Hope Diamond.

Dr. Jeffrey E. Post, a native of Wisconsin, received Bachelor of Science degrees in geology and chemistry from the University of Wisconsin - Platteville, and his Ph.D. in chemistry, with a specialty in geochemistry, from Arizona State University. READ MORE…

Hands on with The New Blues

We learned about two new gem discoveries and the persistence it took to find out what they really are! We heard when, where and how they were discovered, how they were accurately identified, and how they differ from other gems that are similar in appearance. We had a chance to be among the first to handle and examine wonderful samples of the material. In addition, speaking of blue, wee saw and examined fine quality sapphires (and not just blue) from the reactivated mining efforts at Rock Creek, Montana.

A Miner's Dream—Discovering a NEW Gem!

Yianni Melas, Gem Explorer

Most miners pray they'll find a new source of a rare and/or valuable gem or mineral, but the idea of finding a NEW gem is rarely even in their conscious mind! Yianni Melas took us into his world – searching for gems and minerals. Yianni told us, "I explained the circumstances surrounding this discovery of the first and one of the only NEW gems discovered in this century, and for almost 50 years! What took me to that part of the world? What geographic and geologic conditions are important? What is the process once you've found something that you believe, HOPE, is something never before unearthed? I answered these and other questions all gemologists and rock-hounds have…on some level…whether living vicariously through the gems and jewels with which they work, or hoping to find a treasure themselves!"

Apache Blue Stone

Warren Boyd, FGAC, BSC, FCGmA, FGA (bio)

There are very interesting rocks and minerals on and near the San Carlos Indian Reservation in Arizona, including peridot, turquoise, chrysocolla and garnets. Recently another gemmy-looking material was discovered, one that is similar in appearance to both turquoise and chrysocolla, but also different; it is being called Apache Blue Stone. Testing has shown it has different gemological characteristics from either. We discovered whether this is a new gemstone or a new species, or a new color of a known species. Experienced geologists, mineralogists and gemologists realize that the answer often is not easy. Warren shared his experiences in the quest for gems and the thrill of finding something "new" and unexpected and explained what characteristics to look for to identify this material, and provided samples from this exciting new find for you to handle and examine.

In addition, he provided an update on new developments connected with mining for sapphires from Rock Creek, Montana. As a principal of Potentate Mining, LLC, Warren told us what the recent mining efforts at Rock Creek have brought to the surface, in an amazing variety of colors and significant sizes reaching 40 carats. We had the opportunity to see and examine samples in a variety of colors, and both rough and polished.

Claire Mitchell

Separating Similar Looking Stones

Claire Mitchell, FGA, DGA - Gem-A (bio)

As gemologists, we all "sight id" from time to time, but what if you have several stones similar in appearance sitting in front of you? Can you separate them visually? Eighteen students used hand-held tools to make those separations on several groups of look-alikes. Always a useful exercise with lasting results, this class greatly benefited newer gemologists and held surprises for seasoned veterans.

This was an AGA Pilot Workshop - Our first attempt of a break-out session that tested the waters for future AGA conferences. Other attendees enjoyed "The Fabled Viking Sunstone" with Elise Skalwold.

The Fabled Viking Sunstone

Exploring the Optical Phenomena of Pleochroism and Birefringence

Elise A. Skalwold, Cornell University (bio)

The intriguing theory of the Viking's use of a coveted stone to find their way in arctic waters has its roots in the ancient Viking Sagas, optical mineralogy, and in practical application by modern navigators. The proposed minerals thought to be the Fabled Viking "Sunstone" are excellent models for understanding the optical phenomena of pleochroism and birefringence - the very properties which make them useful for navigation are also those which make them valuable as lapidary and gem materials today. There are several candidates for the stone, among them are "Iceland Spar" calcite of which a coveted optical quality was found abundantly in Iceland, and the blue variety of the mineral cordierite, found in Norway and popularly known as "Viking's Compass" and as the gem "iolite." The former is explored in Elise's 2015 paper "Double Trouble: Navigating Birefringence" published by the Mineralogical Society of America, while the latter is featured in her paper "Blue Minerals: Exploring Cause & Effect" published in the special 2016 January/February issue of Rocks & Minerals magazine.

It was a practical lesson in mineral optics from ancient Viking mariners for today's gemologists!

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