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Chameleon diamond before and after heating

Chameleon Diamond with Nickel Absorption Band

Troy Ardon, July 25, 2014

A rare chameleon diamond is examined in GIA's Carlsbad lab.

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.

A Repaired Diamond

Troy Ardon, August 9, 2018

A marquise-cut diamond is found to have been broken and reassembled with an unknown adhesive.

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.

Diamond with uneven “lizard skin” surface texture.

Lizard Skin on Deformed Diamond

Evan M. Smith and Paul Johnson, January 26, 2018

The surface texture of a diamond is affected by the gemstone’s structure.

187.66 “cape” diamond from the Diavik mine

Examination of the Largest Canadian Diamond

John King, Kyaw Soe Moe, and Wuyi Wang, August 3, 2016

GIA examines a 187.66 ct pale yellow diamond from Diavik, the largest rough diamond ever found in Canada.

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.

Fancy yellow 0.40 ct type Ib CVD-grown synthetic diamond

Yellow CVD Synthetic Diamond

Kyaw Soe Moe, Wuyi Wang, and Ulrika D’Haenens-Johansson, July 25, 2014

A Fancy yellow type Ib CVD-grown synthetic diamond undergoes testing at the New York lab.

Mixed-Type Cape Diamond

Martha Altobelli and Paul Johnson , October 31, 2014

A Fancy orangey-yellow “cape” diamond featured an unexpected 480 nm band, a defect normally associated with orange colour.

Xenotime Inclusion in Yellow Diamond

Kyaw Soe Moe, Martha Altobelli, and Paul Johnson , October 31, 2014

Presents what is believed to be the first report of a xenotime inclusion in gem-quality diamond.

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