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
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
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
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
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
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
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