Research & News
Chipping Away at the 1,109 ct Lesedi La Rona
Graff reveals the first polished diamonds produced from the Lesedi La Rona, one of the largest pieces of rough ever mined. Plus, other market news.
Dreher Carvings: Gemstone Animals from Idar-Oberstein
Review of Dreher Carvings: Gemstone Animals from Idar-Oberstein by Wilhelm Lindemann, Will Larson, and Ekkehard Schneider.
15 Carat HPHT Synthetic Diamond
A synthetic diamond seen in the Carlsbad lab is the largest faceted lab-grown diamond examined by GIA.
Nephrite Bracelet with Filled Cavity
A jade bracelet contains unusual fillers, used to create a smooth surface.
Cat’s-Eye Rock Consisting of Jadeite and Amphibole
Raman spectroscopy reveals that a green bead, showing chatoyancy on one side, comprises jadeite and amphibole.
Uncommon Parallel Color Zoning in a Chameleon Diamond
A diamond examined in the Carlsbad lab shows chameleon coloring in an unusual pattern.