Al Gilbertson, Benjamin Gudlewski, Mary Johnson, George Maltezos, Axel Scherer, and James Shigley
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 MoreBrendan M. Laurs, Thomas W. Overton
This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.
Read MoreThomas W. Overton and James E. Shigley, March 1, 2008
Modern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.
Read MoreRizwan U. A. Khan, Philip M. Martineau, Bradley L. Cann, Mark E. Newton, Harpreet K. Dhillon, and Daniel J. Twitchen
In response to heat and UV exposure, some synthetic diamond gemstones grown by chemical vapor deposition exhibit large, reversible changes in colour.
Read MoreInga A. Dobrinets and Alexander M. Zaitsev
HPHT-treated type I diamonds of various colours may exhibit unusually intense fluorescence at the facet edges and junctions.
Read MoreIlene M. Reinitz, Mary L. Johnson, September 1, 2001
This second major article in a three-dimensional modelling study analyses fire – the visible extent of light dispersed into spectral colours.
Read MoreHenry O. A. Meyer and Edward Gübelin, September 1, 1981
The first substantiated identification of corundum (var. ruby) occurring as an inclusion in natural diamond is presented.
Read MoreT. Scott Hemphill, Ilene M. Reinitz, Mary L. Johnson, and James E. Shigley, September 1, 1998
A mathematical model which can analyse how appearance factors depend on proportions.
Read MoreWilliam C. Kerr, September 1, 1982
Introducing a new technique in diamond cutting that virtually eliminates the "bow-tie" effect.
Read MoreJohn I. Koivula, Robert C. Kammerling, June 1, 1989
This 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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