GIA Names New Mineral Crowningshieldite

By Rapaport News / October 10, 2018 / www.diamonds.net / Article Link

RAPAPORT... The Gemological Institute of America (GIA) has discovered anew mineral while studying flaws in large diamonds from the Leteng mine. The organization named the substance crowningshieldite afterG. Robert Crowningshield. The 50-year GIA veteran and pioneer of gemologicalresearch wrote the first report on gem-quality laboratory-grown diamonds in1971, the GIA said Tuesday. Crowningshieldite is a nickel sulfide mineral with ahexagonal crystal structure, and forms when diamond inclusions undergo chemicalmodifications. GIA research scientist Evan Smith and his team, together withresearchers at the University of Padova, identified the compound in two stonesfrom Gem Diamonds' mine in Lesotho, which is known for producing sizeable diamonds.They came across the mineral while examining inclusions in CLIPPIR (Cullinan-like,large, inclusion-poor, pure, irregular and resorbed) diamonds, a variety oflarge, high-quality, type IIa stones that form at significantly greater depthsthan most diamonds do. "Discoveries such as this propel our understanding ofdiamonds and the earth forward," said Tom Moses, the GIA's executive vicepresident and chief laboratory and research officer. "This is why research isthe cornerstone of GIA's mission. I can think of no better way to honor Mr.Crowningshield's legacy." The International Mineralogical Association acceptedcrowningshieldite as a mineral on September 18, the GIA added. Main Image: Diamond with crowningshieldite. Right: G. Robert Crowningshield. (GIA)