The Identification of Artificial Colouration in Diamond
The source of colour in some diamonds, particularly fluorescent green and some yellow stones, can be very difficult to identify despite increasing knowledge about the radiation-related bands seen in the visible spectra of diamonds.
Strong Colour Zoning in Diamond Reflects Complex Growth Environment
A report on a 2.08 ct emerald-cut diamond graded as fancy dark orangey brown.
A Large Irradiated Green-Yellow Diamond
GIA's identification of a large diamond as artificially irradiated based on careful spectroscopic analysis and lab database review.
Large synthetic moissanite with silicon carbide polytypes
Examination of the properties of a synthetic moissanite specimen submitted as a black diamond.
Separation of Black Diamond from NPD Synthetic Diamond
DiamondView is used to differentiate a Fancy black natural diamond from its NPD synthetic counterparts.
Identification of HPHT-Treated Yellow to Green Diamonds
Greenish yellow to yellowish green HPHT-treated diamonds exhibited highly saturated body colour, well-defined brown to yellow octahedral graining and visual evidence of heating, among other characteristics.
Lab-Grown Coloured Diamonds from Chatham Created Gems
This article compares some of Chatham Created Gems’ synthetic coloured diamonds to natural diamonds and explains the results.
Bright yellow diamonds from Sierra Leone
Examination of strongly yellow diamonds from the Zimmi area of Sierra Leone revealed graphitised feather inclusions.
Xenotime Inclusion in Yellow Diamond
Presents what is believed to be the first report of a xenotime inclusion in gem-quality diamond.
Black diamond with unusual colour origin
This black diamond's colour was produced by natural radiation stains, an unusual cause of colour.