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.
Read More
Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
Read More
This article explores and identifies the changes that type IIa GE POL diamonds experience before and after HPHT annealing.
Read MoreModern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.
Read MoreSynthetic moissanite is much closer to diamond in overall appearance and heft than any previous diamond imitation; this article reports on how to identify and characterise it.
Read More
Several diamonds were treated for the purposes of observation and report with a new laser technique which does not show the typical surface-reaching drill hole.
Read More
HPHT-treated type I diamonds of various colours may exhibit unusually intense fluorescence at the facet edges and junctions.
Read More
Results from spectroscopic analyses of GE POL high-pressure high-temperature (HPHT) annealed nominally type IIa diamonds are presented, and these spectral characteristics are compared with those of untreated diamonds of similar appearance and type.
Read More
Exploration of a chart designed to give jewellers and gemmologists a practical guide to identifying synthetic diamonds as they enter the jewellery trade.
Read MoreGeneral Electric has developed a variety of high-temperature annealing techniques at different pressures for enhancing the optical properties of polycrystalline synthetic diamond films and single-crystal synthetic diamond.
Read More
