Past conferences
Abstracts Library
Low Temperature Heat Treatment of Madagascar Sapphire
One of the challenges facing gemologists today is the detec- tion of low temperature (below 1200°C) heat treatment in corundum (Hughes et al., 2017)
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
HFSE-enriched sapphires of gem quality: A combined FTIR and trace element study and implications for heat treatment detection
Gem-quality sapphires containing ‘exotic’ elements such as Sn, Nb, Zr, Ta, W, are of special interest in gemmological research, as the concentration of these so-called high-fie
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
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
A Photo Survey of Inclusions in Fossiliferous Amber
For many, fossiliferous tree resin, primarily amber, gained wide visibility to the public in 1993 where it was prominently featured in the movie, Jurassic Park
Hurlbutite from Myanmar
A crystal of the very rare mineral hurlbutite originating from Myanmar (without further locality details) was studied and faceted afterwards in two gems, which we also studied
Amber from the Thanbaya Gaing Coal Mine, Minbu Township, Magwe Region, Myanmar
Amber was recently discovered by local coal miners at the Thanbaya Gaing Coal mine located 6.5 km northwest of Padaung village, and about 5 km west of Thanbaya Gaing village
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
Zoisite and its many color
The mineral zoisite is a calcium alumosilicate belonging to the class of silicates, more exactly sorosilicate minerals
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
Geographic Origin Determination of Natural Yellow Sapphires: The Preliminary Study
Determining the geographic origin of yellow sapphires plays a critical role in the gem trade, as origin often dictates both perceived quality and market pricing
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
Application of Fibre Optics Reflectance Spectroscopy (FORS) for the determination of mineral pigments in jasper
The identification of pigments is carried out routinely mostly by X-ray diffraction, FTIR and Raman spectroscopy as well as visible absorption
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
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
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
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-
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
Gem zircon and sapphire age dating and application of origin determination: A study from New England sapphire fields, New South Wales, Australia
Ahmadjan Abduryim, Frederick Lin Sutherland, Terry Coldham, Elena Belousova Download Pdf
