Milky appearance of Geuda sapphire from Sri Lanka
Sri Lanka is famous for gems since several thousand years. Almost corundum varieties have been found in Sri Lanka including the rough of Geuda which has also given considerable att
Low Temperature Heat Treatment of Burmese Ruby
Detection of low-temperature heat treatment (below 1200°C) in ruby and sapphire can present challenges to gemologists, as alterations to the material are often subtle. In this stu
Influence of Irradiation on Colour Modification and Colour Stability of Rubies: A Preliminary Study
Ruby is the chromium-bearing red colour-variety of corundum Al2 O3 . Since historic times, ruby is highly popular in the gem and jewellery market because of its highly saturated re
Crystal structure of nano inclusions in blue sapphire from Diego Suarez, Northern Madagascar
Nano inclusions in unheated blue sapphire (Diego Suarez, northern Madagascar) containing naturally occurring beryllium have been studied. Tabular nano inclusions with a diameter of
Additional Observations on Unstable Color in Padparadscha Sapphires
For the past few years laboratories have been testing the color stability of padparadscha sapphires. It became an issue because we realized that the orange color in some pads was u
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
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
Irradiation treatment and gamma-spectroscopy of morganite
The pink variety of beryl, morganite, is one of the most popular orangey-pink to pink gemstones. Its colour is attributed to manganese, both Mn2+ and Mn3+ (Nassau & Wood, 1968, Woo
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.
Applications of Python for Spectroscopic Data Processing, Analysis and Machine Learning Modeling in Gemmology
Python, a powerful programming tool with extensive scientific computing capabilities, is being increasingly utilized in gemmological science. It is particularly well-suited for pro