Past conferences
Abstracts Library
Challenges in the Detection of Ruby and Sapphire Treatment in the Thai Market
The detection of treatments in ruby and sapphire remains a critical aspect and has become an increasingly complex issue in the gem trade and laboratories alike
Gemological Characteristics of New Transparent Brown Sapphire
A newly observed variety of faceted transparent brown sapphire has recently entered the gem market, prompting gemological attention due to its highly unusual appearance
Noble gas in corundum: interests in gemology
Noble gases —elements of the last column of the periodic table—are chemically defined by their full outer electron shells, making them highly inert and very volatile under ambi
Gems in Hellenistic and Roman Jewellery of Northern Greece: An investigation from the Collections of the Archaeological Museum of Thessaloniki, Greece
This study presents the results of an interdisciplinary archaeogemological investigation focusing on gems embedded in Hellenistic and Roman jewellery from the collections of the Ar
Blue sapphire from Malacacheta of Minas Gerais, Brazil
Malacacheta, located in Minas Gerais, Brazil, is renowned for its alexandrite deposits and com-plex geological setting
Identification of melee size synthetic coloured diamond for jewellery
Synthesis methods to produce large and high-quality dia- mond for jewellery have been improved over the years, and large, colourless faceted stones weighing more than 50 ct have be
Pink to Red and Violet Diamonds from the Argyle Mine, Australia: Properties, Color Origin and Latest Research Results
The Argyle Mine was by very far the largest producer of pink to red diamonds worldwide and the only producer of violet diamonds
Gems in Greece: Geology, mineralogy and crystallizing environment
In the accretionary Hellenides Orogen, gems occur in various rock types of mainly four tectonometamorphic units, the Rhodope- and the Attico-Cycladic massifs, the Pelagonian zone,
History of Garnet Mining and Cutting in the Austro-Hungarian Monarchy
Bohemian garnets, i.e., chromium-bearing pyropes, are found in several jewellery pieces from the Migration Period (circa 400 to 600 A.D.), and only a small number of jew- els conta
Historic Emeralds and their Geographic Origin: A Retrospective Study
When it comes to the geographic origin of gems, curiously enough, historians sometimes put forward provenance without any documentary or scientific proof
Padparadscha Sapphire & heat treatment
In 2018 the Padparadscha engagement ring of Princess Eugenie (Figure 1), the niece of the king, gave a boost to the popularity of the gemstone in the UK
Diamonds from Than Lwin River near Mong Hsu, Myanmar
Sixteen rough diamonds were acquired in 2023 by co-author TTS from a gem dealer linked to Mong Hsu, Shan State, Myanmar
Bertrandite in Emeralds
Over the past few years we have been seeing more and more lower quality stones in the lab. The reasons for this may be related to lack of supply of finer goods, rising prices, the
Shining light on “480 nm band” diamonds: Gemmological characteristics of an unusual group of diamonds with yellow and red luminescence
Fancy colour diamonds that derive their colour from nitro- gen-related defects (such as N3/N2 centers or C-centers) are relatively common and well-studied
Found, Lost, and Found Again: The Geological and Gemological Significance of the Salininha Emerald Deposit, Brazil
The Salininha emerald deposit located in the municipality of Pilão Arcado, Bahia State, represents the first economically significant discovery of gem-quality emer- alds in Brazil
Gem-quality pink fluorite from Planggenstock, Switzerland: chemical and physical properties and a comparison with pink fluorites from other localities
In this study, first results of trace element analyses and various spectrometric investigations on pink fluorites from alpine deposits (Aar and Montblanc Massifs) as well as from t
Fe-Ti charge transfers: A comprehensive review and its applications to minerals and gems
The iron-titanium charge transfer (Fe-Ti CT) is mentioned in numerous articles as the source of the coloration of many nat- ural minerals and some man-made materials, but no global
Colored gemstones of metamorphic origin: Progress report in understanding how they crystallize at depth in East Africa, the Hindu Kush, Pamir Mountains, and the Middle-Urals Ring Structure
It is difficult to reconcile the existence of deposits of trans- parent gems of metamorphic origin with the observation attributed to Robert Boyle (1627–1691) that the best crys-
Automated Data Processing of Raman Spectra for Supporting Spinel Origin Determination
pinel is a highly valued gemstone, with its color and quality influenced by trace-element chemistry and crystal structure. Accurate determination of its geographic origin is crucia
Cross-Cultural Provenance and Characterization of Turquoise Artefacts: A Multi-Analytical Non-Destructive Study of Reshui Tomb Cluster, China (744 AD) and Tepeh Zagheh, Iran (5200–4200 BCE)
Turquoise has long held considerable cultural, economic, and symbolic significance across ancient civilizations, func- tioning both as a prestigious ornament and as a medium of exc
