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)
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
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
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
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
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
Effects of Gamma Irradiation on Ruby and Pink Sapphire and Potential Detection Methods in Gem Labs
Gamma irradiation is a non-destructive and non-invasive treatment method used to enhance the colour and aesthetic appeal of gemstones, such as diamond, topaz, quartz, and sapphire.
An implementation of machine learning in ruby and sapphire origin determination
Country-of-origin is one of the most important value factors of corundum (ruby and sapphire) due mainly to its historical or legendary popularity in the trade. Generally, gemmologi
Color enhancement in yellow sapphire
Natural yellow sapphire is colored by one or the combination of two different chromophores, Fe3+ and the trapped hole-Fe3+ (h• -Fe3+) colour center. Fe3+ chromophore is typically