Real-Time Microradiography of Pearls: A Comparison Between Detectors
Compares the image quality provided by real-time microradiographic imaging (RTX) units fitted with two different detectors: an image intensifier (II) and a flat panel detector (FPD).
Photoluminescence Spectra of Emeralds from Colombia, Afghanistan and Zambia
Compares PL spectroscopy data of 48 emerald samples from three countries to evaluate the usefulness of the technique in geographic origin determination.
Origin Determination of Dolomite-Related White Nephrite through Iterative-Binary Linear Discriminant Analysis
A technique for origin identification based on statistical analysis and LA-ICP-MS spectrometry.
Vanadium and Chromium-Bearing Pink Pyrope Garnet: Characterisation and Quantitative Colorimetric Analysis
This type of pink pyrope garnet, believed to have been mined in Tanzania, shows a distinct colour-change phenomenon resulting from its unique chemical composition.
Fluorescence produced by optical defects in diamond: measurement, characterisation and challenges
How variations in UV lamp output can affect observed fluorescence colour and intensity.
Cutting Diffraction Gratings to Improve Dispersion (“Fire”) in Diamonds
A new microlithography process developed to create high-resolution diffraction grating patterns on portions of certain facets can improve the dispersion of light and thus the amount of “fire” in a diamond.
A Foundation for Grading the Overall Cut Quality of Round Brilliant Cut Diamonds
The GIA diamond cut grading system described here includes the components of brightness, fire, scintillation, polish and symmetry, as well as weight and durability concerns, into a single overall grade for cut quality for standard round brilliants.
Characterisation of “Green Amber” With Infrared and Nuclear Magnetic Resonance Spectroscopy
A peridot-like bright greenish yellow to green gem material called “green amber” has recently appeared in the gem market.
Possible “Sister” Stones of the Hope Diamond
A recent study compares a specially created model of the Hope diamond with recent computer models of the French Blue to determine if other stones could have resulted from either recutting.
Strongly Coloured Pink CVD Lab-Grown Diamonds
Pink CVD lab-grown products can be separated from natural and treated-colour natural pink diamonds by a combination of gemmological and spectroscopic properties, which are explored in this study.