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Explores an exceptional family of diamonds, referred to as “CLIPPIR” (Cullinan-like, Large, Inclusion-Poor, Pure, Irregular and Resorbed), that formed in a super-deep environment.
Read MoreThe 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.
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This article explores and identifies the changes that type IIa GE POL diamonds experience before and after HPHT annealing.
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This article reviews the GIA Laboratory’s history of reporting on certain types of graining which are often the only characteristics present in large, high-clarity, high-colour diamonds.
Read MoreThis article discusses the history and ongoing development of GIA's colour grading system, and explains how its laboratory applies it.
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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 MoreThis second major article in a three-dimensional modelling study analyses fire – the visible extent of light dispersed into spectral colours.
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 MoreHigh-quality CVD-grown diamonds, comparable in colour and clarity to natural diamonds, can be identified using a combination of gemmological and spectroscopic properties.
Read MoreThis article reports on the study of six diamonds, both before and after a filling treatment, and the examination of 12 additional filled stones.
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