Article Search Results

Cape Diamond with Yellow Phosphorescence

Kyaw Soe Moe, Jon Neal, and Paul Johnson, May 8, 2017

A cape diamond examined in the New York lab shows rare yellow phosphorescence.

Decay Kinetics of Boron-Related Peak in IR Absorption of Natural Diamond

Sally Eaton-Magaña, January 27, 2017

The decay of the transient 2800 cm^–1 absorption peak in a Fancy grey diamond is observed.

Coesite Inclusions with Filaments in Diamond

Evan M. Smith, Christopher Vendrell, and Paul Johnson, January 27, 2017

Inclusions with unusual formation are found in a treated Fancy Vivid yellow diamond.

4.29 ct color-treated Fancy brown-pink diamond

Treated Pink Type IIa Diamond Coloured by Red Luminescence

Sally Eaton-Magaña, November 7, 2016

A type IIa colour-treated diamond was graded as Fancy brown-pink under daylight conditions and Fancy purplish grey under incandescent lighting, a colour change that resulted from HPHT annealing and irradiation.

59.88 ct Fancy Vivid yellow irradiated diamond

Very Large Artificially Irradiated Yellow Diamond

Christopher Vendrell and Paul Johnson, November 7, 2016

Examination of a 59.88 ct irradiated yellow diamond, one of the largest irradiated diamonds identified by GIA.

DiamondView image of pink diamond showing two pink spots near the edge of the table facet

Evidence of Focused Beam Irradiation in Treated Pink Diamond

Troy Ardon and Lorne Loudin, November 7, 2016

DiamondView imaging and photoluminescence spectroscopy offered evidence of focused beam irradiation in a pink diamond.

Separation of Black Diamond from NPD Synthetic Diamond

Paul Johnson and Kyaw Soe Moe, August 3, 2016

DiamondView is used to differentiate a Fancy black natural diamond from its NPD synthetic counterparts.

Natural Fancy pink diamond with apparent HPHT synthetic growth structure.

Treated Pink Diamond with HPHT Synthetic Growth Structure

Kyaw Soe Moe and Wuyi Wang, February 1, 2016

A Fancy pink type IIa diamond showing cuboctahedral growth and greenish blue phosphorescence is shown to be a natural, treated coloured diamond.

Yellow HPHT-Processed Rough Diamond

Sally Chan, November 23, 2015

HPHT annealing of a nearly eye-clean yellow natural rough diamond is revealed through spectroscopic analysis.

Intense Blue Diamond with Very High Boron Concentration

Paul Johnson and Wuyi Wang, July 31, 2015

A natural Fancy Intense blue diamond submitted to the New York lab shows the highest boron concentration ever reported in a natural specimen.

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