GIA Knowledge Sessions
The GIA Knowledge Sessions are a series of talks and seminars that engage participants in the most diverse and pressing issues in gemmology today, including gemstone origin, laboratory-grown stones and new discoveries in field gemmology. These webinars are brought to you by GIA staff members with Ph.D.s, field gemmologists, educators and research scientists whose experience and expertise offer a trove of gem knowledge.
The sessions are free and open to the public. Registration in advance is required to attend.
Upcoming Sessions
Webinars in English
19 August 2021 | Minerals Discovered and Named at GIA
10.00 am PDT
Speakers: Nathan Renfro & Dr Aaron Palke
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2 September 2021 | Through the Years: Interesting Discoveries from the GIA Laboratory
10.00 am PDT
Speakers: Dr Sally Magaña & Nathan Renfro
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16 September 2021 | Sapphire Treatments
10.00 am PDT
Speaker: Wim Vertriest
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Webinars in Mandarin
12 August 2021 | The Science of Coloured Diamonds
9.00 pm HKT
Speaker: Dr Sally Magaña
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Past Sessions
Webinars in English
5 August 2021 | Highlights from Gems & Gemology: Spring 2021 Issue
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Curious about what’s inside the latest edition of G&G? From a glimpse into the internal structure of natural pearls to uncovering spinel micro-features, this webinar by Senior Manager of Pearl Identification Dr Chunhui Zhou and Manager of Coloured Stone Identification Nathan Renfro is not to be missed. Tune in as they dive into the latest and greatest content of GIA’s prestigious research publication.
22 July 2021 | A Gemstone’s Journey through the GIA Laboratory
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Ever wonder what happens to your coloured stone as it moves through the GIA laboratory? From submission to photoshoots to advanced testing, each gemstone undergoes several processes before receiving a GIA identification report. Journey with Senior Staff Gemmologist Nicole Ahline as she takes us on a behind-the-scenes look at a gemstone’s journey through our laboratories.
8 July 2021 | Gemstones from the Sea
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Marine treasures such as shells, pearls and corals have been valued by humankind since antiquity. These biogenic gems are produced by marine organisms and possess mineral compositions similar to one another. What is the earliest evidence of human use of these materials? Which mollusc species commonly produce pearls? What is precious coral and what are its major sources? What other biogenic gem materials can be found in our oceans? Dive deep into the source and science of these gemstones with GIA Senior Manager of Pearl Identification Dr Chunhui Zhou.
24 June 2021 | Understanding Jadeite
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Jadeite Jade is the most valuable translucent to opaque gem. How do jadeitites form in nature, and where are their most important sources? What’s the difference between ‘Jadeite Jade’ and ‘Fei Cui’, and what do the terms “A Jade”, “B Jade” and “C Jade” mean in the trade? Tune in as Dr George Harlow from American Museum of Natural History and Xiaodan (Holly) Jia from GIA Hong Kong cover the formation, sources, identification and treatments of this precious gem from an international perspective.
10 June 2021 | Sapphires: From Ceylon to Ethiopia
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Since antiquity, sapphires have symbolised truth, fidelity and the heavens. Not only are they sought-after globally, they are also produced at numerous locales across the globe. The most famed historical sources are of course Kashmir and Ceylon/Sri Lanka, but numerous other deposits, both ancient and modern, have shaped the sapphire trade now. Journey with Manager of Field Gemmology Wim Vertriest as he takes us from the illustrious digs in Yogo, Montana to the massive operations in Australia to the recently discovered sapphire fields of Madagascar in pursuit of these true blue classics.
27 May 2021 | Identifying Mineral Inclusions in Diamonds
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Did you know that diamonds are the perfect time capsules, trapping minerals inside them as they form and bringing these minerals with them to the earth’s surface? The minerals trapped inside diamonds are called inclusions and can affect the clarity of a diamond. To scientists, however, they are treasures, telling much about a diamond’s formation as well as the earth’s geological history and processes. What secrets does your diamond hold? Join GIA Research Scientist Dr Evan Smith as he dives into diamond inclusions and explores the methods used to identify them.
13 May 2021 | The Latest Discoveries from Gems & Gemology
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Curious about recent hot topics from the gem world, such as low-temperature heat treatment of pink sapphires from Madagascar, rose-cut stones in artefacts from the seventeenth century or how to distinguish blue amber from different geographical origins? Dive into the latest issue of Gems & Gemology, GIA’s prestigious scientific journal, with contributors Dr Sally Magaña and Nicole Ahline.
29 April 2021 | Colourless Diamonds
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Colourless natural diamonds or “white” diamonds are admired all over the world for their brilliance and fire and treasured as symbols of romance. But did you know that most colourless diamonds aren’t actually colourless? Many contain subtle hints of yellow, brown or grey. In this webinar, we’ll discuss the causes of colour for diamonds on the D-to-Z scale, trends seen in their quality characteristics and how these diamonds are distinguished. Prepare for a brilliant journey with Dr Sally Magaña, Senior Manager of Diamond Identification, as she dives into the science of one of the world’s most popular gems.
15 April 2021 | X-Rays and Their Use in Gemmology
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Did you know that X-rays not only reveal bones but have applications in gemmology as well? X-rays are used to separate natural pearls from cultured ones and to assist in the origin determination of some gems. This technique is unique in that it can be used on opaque as well as transparent gems and is crucial to some aspects of gem identification. Find out more about X-rays with Nick Sturman, Consultant to GIA, in this latest GIA Knowledge Session.
1 April 2021 | Geology 102 for Gemmologists: The Natural Processes That Form Coloured Gemstones
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Gemstones require extraordinary geological circumstances to form. Not only do different minerals need to meet under the right conditions and crystallise, but certain rare elements also need to be part of the mixture for the crystal to be the right colour. Tune in as Wim Vertriest, supervisor of field gemmology, builds on the earth science introduced in “Geology 101 for Gemologists” to explore how alexandrite and spinel form in the earth’s crust and why pegmatites – an igneous rock that is the source of an incredible variety of gems and mineral specimens – is known as "nature's treasure chest".
25 March 2021 | A Look at Kimberlites: The Volcanoes that Carry Diamonds
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Natural diamonds crystallise at great depths, far deeper than we can dig or drill into the Earth. So how is it that diamonds can be found among us? The answer lies in rare and unusual volcanoes called kimberlites. These deeply seated volcanic eruptions can sometimes pick up diamonds, along with other minerals and rock fragments, and blast them to the surface. Think of kimberlites as lifts that diamonds use to ride up to the Earth’s surface! Tune in as GIA Research Scientist Dr Evan Smith digs deeper into these super-charged volcanoes and uncovers the role they play, not just in transporting gem diamonds, but in revealing the geological workings of the Earth.
18 March 2021 | Green Gemstones: History, Lore and Gemmology
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Throughout history, green gemstones have been associated with fertility, serenity and even luck and jealousy. What is the history behind these associations? In celebration of the season and St Patrick’s Day, spring into the lore, history and science of green gemstones with Research Librarian Judy Colbert and Senior Manager of Research Dr Aaron Palke. Learn about the scientific properties and symbolism of some of the most popular, rare and unique green gemstones in the world!
11 March 2021 | Microfeatures of Gems: Geological Implications
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Inclusions are more than imperfections or clarity characteristics. They can teach us much about gemstones’ journeys and reveal otherwise inaccessible information about the Earth’s formation. What stories do diamond inclusions tell about the Earth’s mantle? What do rutile needles and three-phase inclusions teach us about corundum and emerald, respectively? Follow Manager of Gem Identification Nathan Renfro and Senior Manager of Research Dr Aaron Palke as they offer an up-close look into the microworld of gems and show us how this world reveals secrets about the Earth’s geological processes at large.
4 March 2021 | Colour-Change Diamonds
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Did you know that certain diamonds can temporarily change colour when exposed to heat, ultraviolet light, or even when kept in the dark? Some natural greenish diamonds are known as “chameleon” diamonds due to this property. Other natural pink diamonds and some colour-treated and laboratory-grown diamonds can also change colour in unexpected ways. Before this phenomenon was known, there were stories of customers returning diamonds they purchased because the diamonds turned out to be the “wrong” colour! What exactly causes these interesting diamonds to shift their hues? Find out as GIA senior manager of diamond research Dr Ulrika D'Haenens-Johansson and senior research scientist Dr Mike Breeding dive into the mystery of these ultra-cool gems.
25 February 2021 | Autumn 2020 G&G: D-to-Z Diamonds, Royal Jewel Auctions, Vietnam Field Report and More
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G&G’s most recent issue captured the past, present and future of the gem industry – with an overview of European royal jewellery sales (including the sale of Marie Antoinette’s jewellery), in-depth coverage of D-Z diamond knowledge (such as causes of colour and formation) and a journey into Vietnamese pearl farming. Tune in as G&G contributors Troy Ardon and Nicole Ahline touch upon these and other highlights from the most recent publication of GIA’s prestigious scientific journal.
18 February 2021 | Tangled up in Neon Blue: A Review of Paraíba Tourmaline
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Paraíba tourmaline, discovered in Brazil the 1980s, took the gem world by storm. Neon blue to greenish-blue and coloured by copper, it was a gem unlike any other. It was a pleasant surprise, therefore, when other glowing, copper-coloured tourmalines were discovered in Mozambique and Nigeria in the 2000s. Since then, all tourmalines with these characteristics have been known as Paraíba tourmaline. What is the history behind these finds and the science behind their beauty? Follow Senior Staff Gemologist Dr Yusuke Katsurada as he dives into the unique properties of Paraíba tourmaline as well as how GIA scientists determine the geographical origins of these scintillating stones.
11 February 2021 | Red Gemstones: History, Lore and Gemmology
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Throughout history, certain red gemstones such as ruby, garnet and spinel have been associated with love and romance. What are the science and history behind these associations? In honour of Valentine’s Day and lovers everywhere, GIA Senior Manager of Research Dr Aaron Palke and jewellery designer and author Joanna Joy Seetoo are diving into the properties that have caused certain red gemstones to capture the popular imagination and become ultimate symbols of romance. Whether you’re a lover or just love gemstones, make sure to tune in!
4 February 2021 | Gems of the South-West
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The American South-West has long been known for its distinctive jewellery, with the most iconic perhaps being Native American turquoise jewellery. An integral part of Navajo culture, turquoise beads are given to babies at birth and used in initiation rites and marriage and healing ceremonies. Other gemstones such as opal, mother-of-pearl and onyx have also been cherished throughout this region’s history. How have gemstones shaped the lore and culture of this region? What are the geological conditions that allowed for the formation of these gemstones? And what sets these gemstones apart from those found in other places in the world? Discover all this and more as GIA scientist Aaron Palke and Emerald Tanner take us on a gemmological journey into the rugged American South-West.
28 January 2021 | The History of Engagement Rings
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Rings have been used as symbols of love throughout history, so it is no wonder that they became part of the tradition of proposing marriage. When did the history of engagement rings start, why are engagement rings placed on the “ring” finger and how have their styles evolved through the centuries? Tune in as Kate Waterman, GIA Instructor of Gemmology, takes us on a journey through the history of one of the most meaningful and popular types of jewellery in the world.
21 January 2021 | Natural Rough Diamonds: Crystal Shapes and Surface Features
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Once cut and polished, diamonds of similar size, shape and quality may look similar to the unaided eye. But in their rough form, natural diamonds have distinctive morphologies that tell much about their formation and their volcanic journey to the Earth’s surface. Natural diamonds can form as glassy octahedral crystals, flat macles, in unusual spherical shapes and more. During their volcanic transit up to the Earth’s surface, they also often acquire intricate markings from corrosive fluids. Tune in as GIA Research Scientist Dr Evan Smith unravels the story behind rough diamonds’ unique morphologies.
14 January 2021 | Emerald Sources: The Grass is Always Greener on the Other Side
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Emerald has been coveted throughout human history. Only a handful of deposits were known during antiquity, but today, emeralds are mined all over the globe. Embark on a journey with Supervisor of Field Gemmology Wim Vertriest as he explores the history and evolution of the world’s most important sources of emerald – from Cleopatra’s ancient Egyptian mines to the fabled mines in Colombia to more recent deposits in Ethiopia. This webinar will take you from the mountains of Afghanistan to the savannahs of Zambia, from the frozen Arctic to tropical jungles, detailing how and where people have found one of the most valuable treasures in the world.
7 January 2021 | Natural Yellow & Orange Diamonds
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Yellow and orange diamonds both owe their colour primarily to tiny amounts of nitrogen in their structure. Yet, while yellow diamonds are the most common fancy colour diamonds, orange diamonds are among the rarest. What causes the difference in colour and rarity between yellow and orange diamonds? Join Senior Research Scientist Dr Mike Breeding as he investigates the atomic-scale characteristics that produce the colours of these dazzling gems.
17 December 2020 | Short Takes: Recent Highlights from G&G’s Regular Columns
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GIA’s quarterly academic journal, Gems & Gemology, has relayed a wealth of gemmological knowledge to industry professionals since 1934. In addition to articles on groundbreaking research, each issue contains short but insightful entries in the Lab Notes, Micro-World and Gem News International sections, covering notable gem submissions to the lab, gem inclusion scenes and pressing gem topics from around the world. Explore recent publications on diamonds and coloured stones in these three unique columns with GIA research scientists Dr Sally Magaña and Nathan Renfro and managing editor of Gems & Gemology, Stuart Overlin.
10 December 2020 | Where Do Yellow Type Ib Diamonds Form in Nature?
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Yellow diamonds with isolated nitrogen are rare and dazzling, accounting for less than 0.1% of natural diamonds. This is because, over time under high temperatures, the isolated nitrogen atoms that cause many of these diamonds’ intense yellow colours will aggregate and turn the diamonds pale yellow or near colourless. What allows these rare yellow diamonds to retain their colour? Tune in as GIA Research Scientist Dr Karen V. Smit explores the atomic make-up and geological journey of these stunning treasures.
3 December 2020 | Melee Diamond Analysis
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Melee diamonds are the most prevalent stones in the market, and an integral part of the jewellery industry. They represent a new identification challenge owing to their very small size. With the emergence of laboratory-grown diamonds in larger quantities, the ability to efficiently and accurately separate melee-sized natural stones from laboratory-grown diamonds has become critical. Join GIA Senior Research Scientist Dr Mike Breeding as he explores the world of melee diamond analysis and the unique challenges of these small stones.
19 November 2020 | Behind the Scenes Part II: Untold Stories from GIA Field Gemmology Expeditions
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Field gemmologists are modern-day explorers in the gem world, journeying far and wide to document mining culture and gem geology. Not only is their work instrumental to gem origin research, but it also offers us a fascinating insight into the communities that bring us these dazzling treasures. Join Senior Manager of Research Dr Aaron Palke, Supervisor of Field Gemmology Wim Vertriest and Director of the RTL Gemological Library Robert Weldon as they take us on another thrilling field gemmology journey, narrating stories through highlights from their previously unpublished photograph collection.
12 November 2020 | The Sustainability Minefield: What Does Sustainability Mean in Jewellery and Why Should We Care?
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Ethical jewellery will be as important in the future as digital technology is today, but it is currently a confusing and complex area. Author and journalist Melanie Grant expands on topics discussed in her book, "Coveted: Art and Innovation in High Jewelry", with a panel of experts as part of GIA’s Knowledge Sessions series. She will be joined by Susan Jacques, President and CEO of GIA; Dr Raquel Alonso-Perez, Curatrix of the Mineralogical and Geological Museum at Harvard University; Livia Firth MBE, Founder and Creative Director, Eco-Age; and high jewellery artist Alexandra Mor for what will be a spirited discussion.
5 November 2020 | Laboratory-Grown Coloured Gemstones: Crystal Growth Methods
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Advancements in technology have allowed us to create laboratory-grown gems in greater variety and higher quality than ever before. How are laboratory-grown gemstones such as ruby, sapphire, spinel, alexandrite and emerald produced? And how do the various growth methods affect their quality and appearance? Join Education Operations Technical Adviser Dr Jennifer Stone-Sundberg as she covers laboratory-grown gem history, crystal growth methods for both jewellery and industry use, the market for laboratory-grown gems, as well as ways to identify these man-made gems.
29 October 2020 | Superstitions Surrounding Gems and Jewellery
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Gems and jewellery are more than just beautiful. For millennia, they’ve been fraught with symbolism — thought to contain medicinal powers and be able to ward off evil or bring their wearer joy and good fortune. Some jewels, on the other hand, are the opposite and are rumoured to be cursed! Follow Senior Research Librarian Rose Tozer as she explores the beliefs and superstitions people have held about gems and jewellery throughout history. Learn about “cursed” gems, mourning jewellery, charms, amulets, jewellery symbols, such as the evil eye, and animal motifs, such as bats, scarabs, snakes, skulls, spiders and more!
22 October 2020 | Natural Blue Diamonds
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Natural blue diamonds are among the most valuable and famous of fancy colour diamonds. From the Hope diamond with its fiery phosphorescence to hydrogen-rich diamonds with their intriguing Alexandrite effect, blue diamonds have always captured our imagination. Tune in as Dr Sally Magaña — Senior Manager of Diamond Identification – explores the science of blue diamonds and their close cousins, violet and grey diamonds, and delves into the stories of these legendary stones.
15 October 2020 | Furnaces, Fluxes and Filling: A Review of Ruby Treatment
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Many gems are treated to improve their appearance. While treatments can be controversial, they help provide a market for a wide variety of qualities of natural gemstones, which helps keep the supply chain going. Ruby, the king of gemstones, is no exception to often being treated. The degree of treatment varies from none to minimal to a total make-over and can affect value accordingly. Follow GIA Supervisor of Field Gemmology Wim Vertriest, as he explores common ruby treatments, their results and how to identify them.
8 October 2020 | The Sapphires of Montana
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When the first prospectors set out for the American West, they were looking for gold, and in Montana they found their share. But some of these unwittingly lucky miners also found another dense precious mineral — sapphires. Most of the sapphires found in the 1800s in Montana were only suitable for industrial use. But in the late 1900s, heat treatment processes were developed that made Montana sapphires one of the most important American-mined gems. Join GIA researchers Nathan Renfro and Aaron Palke as they unearth the history and gemmology of these stunning jewels.
1 October 2020 | The Evolution of Laboratory-Grown Diamond Evaluation at GIA
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Both the quality and quantity of laboratory-grown diamonds have increased in the past several years. GIA’s reports for laboratory-grown diamonds have evolved as consumers’ knowledge and interest have grown. What has changed in the 14 years since GIA first started issuing reports for laboratory-grown diamonds? Discover the evolution of these man-made gems and learn about GIA’s new reports for laboratory-grown diamonds with Senior Research Scientist Mike Breeding.
24 September 2020 | The History of Diamond Cutting and Polishing Technology
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Diamond is one of the hardest natural materials on earth, and cutting and polishing it is no simple feat. In recent decades, technological advancements such as laser cutting have greatly enhanced the ease and precision of diamond cutting, but artisans have been polishing diamonds since at least the end of the Middle Ages! How is it even possible to cut and polish this exceptionally hard material? How does human skill unleash a diamond’s brilliance? Discover the answers to these questions and more from GIA Research Scientist Dr Evan Smith as he uncovers the history of diamond polishing and shares his own experience of cutting diamonds for scientific research.
17 September 2020 | Natural Pink Diamonds
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Natural pink to red diamonds are among the rarest and most desired fancy coloured diamonds. How they form is still a mystery — but scientists have observed that the vast majority of pink diamonds have a 550 nm absorption band, which indicates that shear stress and deformation of the crystal structure had occurred while the diamond was deep within the earth. Tune in as Dr Sally Magaña — Senior Manager of Diamond Identification — dives into the science of pink and red diamonds and unravels the mysteries of these enchanting stones.
10 September 2020 | A Comparison of Diamonds and Coloured Stones: Geographical Origin to Geology and More
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Diamonds and coloured stones are often considered to exist in entirely different realms in the gem and jewellery industry. This might partly be due to the fact that they are mined and brought to market so differently. Diamonds are primarily mined in large, industrial-scale operations, while coloured stones such as rubies, sapphires and emeralds are typically produced by smaller-scale, often artisanal, operations. Their quality is also assessed very differently. Nonetheless, both diamonds and coloured stones have helped scientists unlock secrets about Earth’s geology. Tune in as GIA Research Scientist Dr Karen Smit and GIA Senior Manager of Research Dr Aaron Palke reveal why these gems have more in common than you may have imagined.
3 September 2020 | Natural Green Diamonds
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Naturally coloured green diamonds are among the rarest of all coloured diamonds. Unlike other diamonds that get their colour deep in the earth, most green diamonds come into contact with radioactive fluids near the earth’s surface that create structural defects and produce their green colour. Diamonds can also be turned green by irradiation treatment. Can natural green diamonds be separated from their treated counterparts? Unravel their mysteries with Senior Research Scientist Dr Mike Breeding.
27 Aug 2020 | Diving into the GIA 7 Pearl Value Factors™
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While diamonds have four primary areas of assessment (the 4Cs), pearls have seven! These include colour, lustre, nacre, surface and more. Evaluating pearl’s enchanting beauty can be quite complex. Did you know that in addition to bodycolour, some pearls also have overtone and orient? That’s why GIA has developed a systematic technique for evaluating pearls. Follow Senior Staff Gemmologist (Pearls) Akira Hyatt as she explores the GIA 7 Pearl Value Factors™ and its recent updates, as well as introducing the new Cultured Pearl Classification Report.
20 Aug 2020 | Glowing Diamonds: Fluorescence and Cathodoluminescence Imaging of Growth Structures and Defects
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Did you know that roughly 35% of diamonds fluoresce or glow under long-wave UV light? Besides longwave UV radiation, other methods can be used to “excite” diamonds so that even diamonds classified as non-fluorescent will glow. These methods are important to scientists, because a diamond’s glow can reveal unique and colourful growth patterns that help to separate natural diamonds from those that are laboratory-grown. Join us as Senior Manager of Diamond Research, Dr Ulrika D’Haenens-Johansson, shines a spotlight on the importance of fluorescence and cathodoluminescence in diamond identification and research.
13 Aug 2020 | Russia’s Treasure of Diamonds and Precious Stones
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GIA in Carlsbad houses perhaps the world’s most comprehensive collection of materials documenting the history, science, business, and art of gems and jewellery. One of our most valuable works is Aleksander E. Fersman’s Russia’s Treasure of Diamonds and Precious Stones, bought by GIA in 1997. This rare historical catalogue, created at the behest of the Soviet Union to help sell the Romanov family’s jewels, describes treasures such as the crown jewels and regalia of Russia. Follow Senior Research Librarian Rose Tozer as she opens the door to GIA’s archive and unlocks a trove of historical gem and jewellery knowledge.
6 Aug 2020 | The Microworld of Gemstones
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The microscope is one of the most powerful instruments for analysing gems. The inclusions contained within a gem as well as the features found on the surface can reveal a story about that gem. Get an up-close look at the microworld of gems with GIA Manager of Identification (Coloured Stones) Nathan Renfro, and learn about both standard and advanced microscopic techniques as well as the principles of lighting and photomicrography. This microscopic exploration is the beginning to uncovering the secrets hidden within the gemmological microcosm.
30 July 2020 | Diamond Ages: Are Diamonds Forever?
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Older than the dinosaurs and almost as old as Earth itself, diamonds are windows into the mysteries of our planet’s continuing geological evolution. How old are the oldest diamonds and are diamonds still forming now? How are diamonds dated and why doesn’t carbon dating work on them? Join GIA Research Scientist Dr Karen Smit and Senior Staff Scientist Dr Steven Shirey of the Carnegie Institution for Science’s Earth and Planets Lab as they explore diamond dating and what diamonds teach us about the Earth.
23 July 2020 | The Art of Photographing Minerals, Gemstones and Jewellery
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Robert Weldon, director of GIA’s library, has photographed some of the most extraordinary jewellery and gem specimens in the world. His work has graced the pages of “Splendour and Science of Pearls” and GIA’s scholarly journal, Gems & Gemology, to name just a few. Gems are known for the spectacular way they interact with light — glowing with colour, sparkling or displaying fascinating phenomena. How do you capture their essence with a single shot? Peer through Robert Weldon’s camera lens as he talks tools, lighting, props and everything gemmology.
16 July 2020 | The Science Behind Fancy Colour Diamonds
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Coloured diamonds are priceless marvels of nature. From red and pink to green, blue, purple and brown, they exist in a rainbow of colours, caused by factors such as geological forces, exposure to radioactive fluids or minerals, or atoms from trace elements being trapped in a diamond’s crystal lattice. Dazzled by these mysterious treasures? Tune in as Dr Sally Eaton-Magaña — Senior Manager of Diamond Identification — explores the science of diamond colour and how fancy colour diamonds are created within the earth.
9 July 2020 | GIA Research — Not Just for Scientists
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Ever wonder who plans GIA courses and what goes into them? Gemmology is part science, part art, part business. That’s why our education is fuelled by GIA research — including our unique field gemmology explorations — as well as informed by the information and experience of people throughout the industry. Whether you are a GIA alum or are simply curious about GIA education, tune in to “GIA Research — Not Just for Scientists” presented by Dr Tao Hsu — Director of Global Professional Development — to get a behind-the-scenes look at how we design our world-respected curriculum.
2 July 2020 | Geology 101 for Gemmologists: The Natural Processes that Form Coloured Gemstones
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What makes a gemstone rare and why are some gems rarer than others? The answer lies in gemstone geology. Some gems, such as emerald, require extraordinary geological circumstances to form. Not only do different rock types need to meet under the right conditions and crystallise, but certain rare elements often also need to be part of the mixture for the crystal to be the right colour. Wim Vertriest, supervisor of field gemmology, covers the chemistry of the Earth’s crust and the geological criteria for forming rubies, sapphires and some of the world’s most valuable gems.
25 June 2020 | Diamond Colour Treatment and Its Identification
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Natural fancy colour diamonds acquire their colour in a variety of ways, such as through trace elements, radiation and crystal lattice distortion. What about laboratory-grown fancy colour diamonds? Or natural diamonds that have undergone treatment to change or improve their colour? How are they created or treated and how do GIA scientists detect them? Tune in as Dr Wuyi Wang, vice president of research and development, offers insight into diamond coloration, treatment techniques and the identification challenges facing gemmologists today.
18 June 2020 | Tools of the Trade: The Advanced Analytical Equipment Used in GIA Laboratories
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From loupes and microscopes to more advanced instrumentation, researchers use a host of tools to help them identify and analyse gems. Curious about how spectrometry helps scientists measure chemical impurities? Want to learn about laser ablation inductively coupled plasma mass spectrometry? Follow senior manager of research, Dr Aaron Palke, on a behind-the-scenes tour of the tools used in a modern gemmological laboratory, seeing with new eyes how scientists employ advanced analytical equipment to identify and characterise the gemstones that pass through GIA.
11 June 2020 | Diamond Exploration & Mining
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Each year, mining companies invest hundreds of millions of pounds globally in finding new diamond deposits. Few of these explorations actually succeed. How do geologists decide where to look, what tools do they use to home in on diamonds and how do they know if they’ve discovered a commercially viable diamond mine? And once mining begins, what does diamond mining look like? GIA Research Scientist Dr Evan Smith digs deeper into the process of unearthing these scintillating gems.
4 June 2020 | An Overview of Pearl Identification: Techniques and Challenges
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The nacreous and non-nacreous layers that make up a pearl conceal many mysteries but also offer many clues to the gem’s origin — for those who can read them, that is. How do we know if a pearl is natural or cultured, saltwater or freshwater and which variety of mollusc created it? Furthermore, how do we detect treatments, especially to enhance the colour? GIA Manager of Pearl Identification Dr Chunhui Zhou dives into pearl identification methods. From simple observation to X-ray radiography and DNA barcoding, learn how and why GIA scientists analyse these unique and lustrous treasures.
28 May 2020 | Behind the Scenes: Untold Stories from GIA Field Gemmology Expeditions
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GIA field gemmologists journey far and wide to document gem geology and mining techniques. Behind their endeavours are moving stories, humorous anecdotes and fascinating local lore. Senior Manager of Research Dr Aaron Palke, Supervisor of Field Gemmology Wim Vertriest and Director of the RTL Gemological Library Robert Weldon offer an exclusive look at GIA field gemmology expeditions through previously unpublished photographs.
21 May 2020 | An Exclusive View of the Jade Auction
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Jadeite is the only coloured gemstone whose auction price can rival that of ruby, emerald and sapphire. What is jadeite’s enduring appeal and what factors determine this gem’s value? Journey with Dr Tao Hsu, geologist and director of global professional development for GIA education, as she explores a jadeite auction at the exclusive Myanma Gems Emporium in Myanmar — the country that produces over 90% of the world’s jadeite. Pick up insider tips and knowledge along the way!
14 May 2020 | Laboratory-Grown Diamonds from China
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China is the world’s largest producer of laboratory-grown diamonds for industrial use and is now a significant producer of gem-quality laboratory-grown diamonds. What impact do Chinese laboratory-grown diamonds have on diamond prices and the jewellery industry? Find out as Dr Wuyi Wang, GIA vice president of research and development, breaks down how and why laboratory-grown diamonds are produced in the world’s second-largest economy.
7 May 2020 | Rubies: Connecting Sources, Treatment and Science
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Known as “the king of precious stones”, untreated rubies are some of the most valuable coloured gems in the world. Find out why as Wim Vertriest, supervisor of field gemmology at GIA Bangkok, explores the mining, treatment, lore and politics of these legendary gems.
30 April 2020 | Fascinating World of Pearls and Shells
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We’re shelling out pearl knowledge with a webinar by Nick Sturman, senior manager of global pearl services at GIA. Do all bivalves, including oysters, clams and mussels, produce pearls? Which pearl types are the most popular and where are they found? Travel with us as we dive into the world of these rare organic treasures.
23 April 2020 | GIA’s Field Gemmology Programme: A Research Based Approach to Origin Determination
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Senior manager of research, Aaron Palke, Ph.D., expounds on advanced research techniques to determine gemstone origin and how traceability may be the next challenge GIA undertakes.
16 April 2020 | Laboratory-Grown Diamonds: Updates and Identification
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GIA senior research scientist, Dr Mike Breeding, wants to tell you the story of laboratory-grown diamonds. If all diamonds are made of carbon, what separates laboratory-grown from natural?
9 April 2020 | The Unique Story of Natural Diamond
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Research scientist, Dr Evan Smith, explores the origin of natural diamonds and discusses their significance from the perspective of Earth science.
Webinars in Mandarin
15 July 2021 | A Review of Spinel: Treatment and Geographical Origin
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Spinel, sometimes referred to as "History's Most Underappreciated Gem", was often confused with ruby and sapphire. What are the latest discoveries about this unique gemstone in modern gemmology? Follow GIA Hong Kong Supervisor of Identification (Coloured Stone) Xiaodan Jia as she dives into the gemmologcial characteristics and major sources of spinel.
20 May 2021 | GIA iD100™: Quickly and Easily Distinguish Natural from Laboratory-Grown Diamonds
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Want to know a fast and accurate way to distinguish natural diamonds from laboratory-grown diamonds and diamond simulants? Discover how the GIA iD100™ uses fluorescence spectroscopy combined with automatic spectral analysis algorithms to screen loose and mounted diamonds. This cutting-edge device can be used to distinguish D to J colourless diamonds and can also detect multi-treated pink diamonds. Join Senior Research Scientist of Instrument Development Dr Tsung-Hang Tsai to explore the optical spectroscopic and imaging techniques that GIA scientists use to analyse diamonds on a daily basis and that are also incorporated in the GIA iD100™.
22 April 2021 | Laboratory-Grown Diamonds in China, their Treatments and Associated GIA Services
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Dr Ulrika D’Haenens-Johansson, Senior Manager of GIA Diamond Research, and Dr Wei Li of Chongqing Daimeng Youshi Technology Co., Ltd. will review the progress on laboratory-grown diamonds in China. Dr Li will share his expertise on their treatment, revealing how it is possible to create beautiful laboratory-grown diamonds spanning the full rainbow of colours. They will also discuss associated GIA services that support the confident and transparent purchase of laboratory-grown diamonds, such as the recently updated Laboratory-Grown Diamond reports.
18 February 2021 | GIA - 90 Years of Innovation
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Established in 1931, GIA marks its 90th anniversary this year. In our almost century-long history, we have created the 4Cs of diamond quality and the GIA International Diamond Grading System™, and developed pioneering instrumentation for diamond grading. What scientific breakthroughs led GIA to where it is now, and what’s next? Join Dr Wuyi Wang, GIA’s vice president of research and development, as he explores 90 years of innovation in diamond grading and identification, and instrument development, followed by his predictions for the challenges and opportunities ahead.
21 January 2021 | GIA Research — Not Just for Scientists
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Ever wonder who plans GIA courses and what goes into them? Gemmology is part science, part art, part business. That’s why our education is fuelled by GIA research — including our unique field gemmology explorations — as well as informed by the information and experience of people throughout the industry. Whether you are a GIA alum or are simply curious about GIA education, tune in to “GIA Research — Not Just for Scientists” presented by Dr Tao Hsu — Director of Global Professional Development — to get a behind-the-scenes look at how we design our world-respected curriculum.
10 December 2020 | Diving into the GIA 7 Pearl Value Factors™
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While diamonds have four primary areas of assessment (the 4Cs), pearls have seven! These include size, shape, colour, nacre, lustre, surface and matching. Evaluating pearl’s enchanting beauty can be quite complex. Did you know that in addition to bodycolour, some pearls also have overtone and orient? That’s why GIA has developed a systematic technique for evaluating pearls. Follow GIA Senior Manager of Pearl Identification Dr Chunhui Zhou as he explores the GIA 7 Pearl Value Factors™ and its recent updates and introduces the new Cultured Pearl Classification Report.
12 November 2020 | Understanding “Fei Cui”: Jade Identification and Nomenclature
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Jade is the most valuable translucent to opaque gem, and GIA, as well as the modern market, has established unique standards for evaluating its quality. What’s the difference between "jade" and "fei cui" and what do the terms “A Jade”, “B Jade” and “C Jade” mean in the trade? Tune in as Senior Staff Gemmologist Xiaodan Jia from GIA Hong Kong covers the history, identification, treatments and nomenclature of this precious gem from an international gemmological perspective.
15 October 2020 | Treatments in Corundum
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Rubies and sapphires are some of the most sought-after gems in the world. As a result, a wide variety of methods have been invented to treat them to improve colour and clarity. Common treatments include assemblage, oil filling, dyeing, glass filling, lattice diffusion, heating and irradiation. What are the telltale signs of treated corundum? And how do GIA gemmologists detect these treatments? Follow GIA Carlsbad Research Associate, Ziyin Sun, as he covers knowledge crucial to unmasking treatments in these beloved gems.
17 September 2020 | Laboratory-Grown Diamond Identification
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In recent years, laboratory-grown diamonds have been produced in commercial quantities and qualities and are being used more and more in jewellery. Impossible to distinguish from natural diamonds with the unaided eye, laboratory-grown diamonds can only be detected through advanced analysis by a gemmological lab. Tune in as GIA Vice President of Research and Development Wuyi Wang talks in depth about laboratory-grown diamonds, including post-growth treatments and the identification methods used to detect these gems.
20 August 2020 | A Closer Look at Sapphire: Treatment and Geographical Origin
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Sapphire has been cherished for thousands of years for its remarkable colour, lustre and hardness. What are the most popular modern treatment processes and how do they improve the appearance or durability of a sapphire? Where are sapphires mined and how do scientists track their provenance through inclusion study and advanced testing? Tune in as Jia Xiaodan, Senior Staff Gemmologist of Coloured Stones at GIA Hong Kong Laboratory, shares the most recent developments on sapphire treatments and origin determination.
6 August 2020 | Major Gem Producing Areas Around the Globe
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The world’s most productive gem sources are constantly changing. Old mines dry up while new ones are found. Which are currently the most productive big three (ruby, emerald and sapphire) mines? Where is the best Paraíba tourmaline found? Fuelled by data collected from 95 GIA field gemmology expeditions to 21 countries, Director of Global Professional Development, Dr Tao Hsu, offers an overview tour of the world’s most famed and productive gem sources.
23 July 2020 | An Overview of Pearl Identification: Techniques and Challenges
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The nacreous and non-nacreous layers that make up a pearl offer many clues to the gem’s origin. How do we know if a pearl is natural or cultured, saltwater or freshwater and which variety of mollusc created it? Furthermore, how do we detect treatments? GIA Manager of Pearl Identification Dr Chunhui Zhou dives into pearl identification methods. From simple observation to X-ray radiography and DNA barcoding, learn how and why GIA scientists analyse pearls.
9 July 2020 | Advanced Analytical Techniques
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Gemmology has come a long way as a field since it began in the early 1900s. Initially, gemmology’s question was: “what is this stone?” Then: “is this stone laboratory-grown or natural?” and then “has this stone been treated?” Now, the all-consuming question is: “which country is this stone from?” As the industry evolves and our knowledge expands, so does our desire to learn more. That’s why advanced analytical techniques have become indispensable to modern gemmology. Tune in as GIA research associate, Ziyin Sun, explores the instruments and techniques used to address gemmology’s most pressing questions.
23 June 2020 | The Fascinating World of Pearls and Shells
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We’re shelling out pearl knowledge with a webinar by GIA Manager of Pearl Identification Dr Chunhui Zhou. Do all bivalves, including oysters, clams and mussels, produce pearls? What are conch and melo pearls? Which pearl types are the most popular and where are they found? From the seas of Australia, Tahiti and Thailand to the waters of China, travel with us as we dive into the world of these rare organic treasures.
11 June 2020 | An Exclusive View of the World’s Biggest Jade Auction
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Jadeite is the only coloured gemstone whose auction price can rival that of ruby, emerald and sapphire. What is jadeite’s enduring appeal and what factors determine this gem’s value? Journey with Dr Tao Hsu, geologist and director of global professional development for GIA education, as she explores a jadeite auction at the exclusive Myanma Gems Emporium in Myanmar — the country that produces over 90% of the world’s jadeite. Pick up insider tips and knowledge along the way!
28 May 2020 | Laboratory-Grown Diamonds from China
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China is the world’s largest producer of laboratory-grown diamonds for industrial use and is now a significant producer of gem-quality laboratory-grown diamonds. What role does China play in the laboratory-grown diamond market and what impact does it have on the natural diamond market and the jewellery industry? Find out as Dr Wuyi Wang, GIA vice president of research and development, breaks down how and why laboratory-grown diamonds are produced in the world’s second-largest economy.
Other GIA Virtual Events
Past GIA Tokyo GemFests (Japanese)
6 January 2021 | 29th Tokyo GemFest: The Gemmological Characteristics and Earth Science of Jadeite
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Jadeite has been prized in Asia, South America and Central America since ancient times, and it is presently well-known as one of the most popular gemstones. Recent scientific research on jadeite also suggests that jadeite is the key to understanding the evolutionary history of the Earth. In this seminar, we will introduce the basic gemmological characteristics of jadeite, including Japanese jadeite, and its importance to Earth science.
10 December 2020 | 28th Tokyo GemFest: Recent Coloured Stone Market Trends in Japan
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Recently, rare and interesting coloured stones have been gaining popularity in the domestic market. In this seminar, Mr Oyama will explain and analyse the market trends of the all-time most famous coloured stones but also those coloured stones which have recently been gaining popularity in Japan.
25 November 2020 | 27th Tokyo GemFest: How to Transform a Basic Jewellery Brand into a Luxury Brand
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In this presentation, Dr Shinya Nagasawa, Professor of Waseda University, will explain and share his long-standing research on luxury branding and marketing. He will share his view of how to transform Japanese jewellery brands into global luxury brands to make them competitive.
15 October 2020 | 26th Tokyo GemFest: Ethics and Sustainability of the Jewellery Industry
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Recently, terms such as “sustainable” and “ethical” have become popular in the fashion industry. As millennials emerge as major consumers, ethics and sustainability will also become important in the jewellery industry. This presentation focuses on the global movement towards ethics and sustainability within the jewellery industry by introducing concepts that HASUNA uses in its brand.
9 October 2020 | 25th Tokyo GemFest: Advanced Analytical Equipment Used in GIA Laboratories
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In recent years, there have been great advancements in gem identification techniques. Standard gemmological tools are not always effective when identifying treated stones and laboratory-grown gems, or when determining geographical origins. Highly advanced analytical techniques used to determine concentrations of trace elements are now necessary for origin determination. This seminar discusses how GIA's laboratories have progressed by using new analytical techniques.
30 September 2020 | 24th Tokyo GemFest: Understanding CVD Diamond – Its History and Application
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Diamonds grown by chemical vapour deposition synthesis, known as CVD, are relatively new to the market and have attracted recent attenion. Japan developed CVD synthesis for diamonds in the early 1980s and has since been a global leader in CVD diamond research. In this seminar, Dr Tsugawa, who has been involved in CVD diamond research for years and currently works for the world-leading manufacturer of diamond CVD systems, will discuss the history and the current applications of CVD synthesis for diamonds.
19 August 2020 | 23rd Tokyo GemFest: Extraterrestrial Gems: Attraction of Meteorites
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Meteorites are visitors from space whose origins are asteroids. They formed 4.56 billion years ago when our solar system was born. Some rare meteorites came from the Moon and Mars. In this seminar, Dr Mikouchi will talk about the attraction of meteorites from the viewpoints of their mineral beauty and the hidden history of the birth of the solar system and its evolution.
5 August 2020 | 22nd Tokyo GemFest: Emeralds from the Ural Mountains
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The Urals in Russia used to be the most productive emerald deposit in the 19th and early 20th centuries. Reviving emerald production in Mariinsky Priisk mine is bringing fine Russian emeralds back into the limelight. This seminar covers the geological background of emerald deposits and information from the GIA field gemmology trip that the speaker joined in 2019.
8 July 2020 | 21st Tokyo GemFest: Identification and Treatments of Coloured Stones
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The treatments of coloured stones during the gem and jewellery trade process are carried out to improve the appearance and colour of gemstones. Such treatments include heat treatments of ruby and sapphire, clarity enhancements of emerald, and a combination of bleaching and dying of jade. During this presentation, the types of coloured stone treatments and identification methods will be introduced.
17 June 2020 | 20th Tokyo GemFest: Geographical Origin Determination of Ruby
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Ruby is produced in a variety of localities, ranging from Southeast and Central Asia (including Myanmar), to East Africa. This seminar will introduce GIA's efforts in geographical origin determination and will share the latest findings on rubies.
29 May 2020 | 19th Tokyo GemFest: Geographical Origin Determination of Paraíba Tourmaline
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Blue to green copper-bearing tourmaline, known as Paraíba Tourmaline, has been quite popular in the coloured gemstone market for the past three decades. This seminar will review its gemmological characteristics and discuss GIA’s geographical origin determination.
21 May 2020 | 18th Tokyo GemFest: Laboratory-Grown Diamonds Basics and Updates
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Recently, we have seen an increase in the use of laboratory-grown diamonds in jewellery. In this seminar, we explain the synthesis methods and the characteristics of laboratory-grown diamonds that are useful for identification. We also introduce some of the latest laboratory-grown diamonds examined at GIA.
8 May 2020 | 17th Tokyo GemFest: Gemmological Characteristics and Origin Identification of Alexandrite
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Alexandrite is a famous gemstone that shows a beautiful colour change effect. In this seminar, we introduce the basic gemmological characteristics of alexandrite and GIA’s Identification and Origin Report service which started in early 2019.
Past GIA Gemstone Gatherings
23 September 2020 | Traditional vs. Non-Traditional Colour Terms Applied to Sapphires
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Over the past five years, the sapphire market has seen an increase in demand for two hue ranges seen in sapphires — rO-oY(peach) and bG-gB (teal). This session will give attendees the tools to understand and articulate clearly to their customers the subtle differences among pinkish-orange, orangish pink and Padparadscha stones. Sheahan will also give clear-cut descriptions for G (green), bG-gB (teal) and yellow-green sapphires. Through reviewing a number of graphs covering time, colour, consumption and shifting prices, attendees will gain an in-depth understanding of what’s causing this movement towards fancy-coloured sapphires from traditional blue stones. Ultimately, this session will help attendees understand their customers’ requests/needs more clearly and help them close sales on these unique, fancy-coloured sapphires.
24 June 2020 | 115th Gemstone Gathering: Precision Cut: How, Why and When?
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The expression “precision cut” has become very popular over time. Victor Tuzlukov will explain his point of view of the term "precision cut" and share his inspirations that led him to become a professional cutter. He will also lead a discussion on the advantages and disadvantages of the precision cut, how such lapidary work affects the gemmologist, and how to judge whether existing fashioned stones would benefit from re-cutting.
