GIA Names New Mineral Crowningshieldite

RAPAPORT… The Gemological Institute of America (GIA) has discovered a
new mineral while studying flaws in large diamonds from the Letšeng mine.



The organization named the substance crowningshieldite after
G. Robert Crowningshield. The 50-year GIA veteran and pioneer of gemological
research wrote the first report on gem-quality laboratory-grown diamonds in
1971, the GIA said Tuesday.


Crowningshieldite is a nickel sulfide mineral with a
hexagonal crystal structure, and forms when diamond inclusions undergo chemical
modifications. GIA research scientist Evan Smith and his team, together with
researchers at the University of Padova, identified the compound in two stones
from 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 of
large, high-quality, type IIa stones that form at significantly greater depths
than most diamonds do.


“Discoveries such as this propel our understanding of
diamonds and the earth forward,” said Tom Moses, the GIA’s executive vice
president and chief laboratory and research officer. “This is why research is
the cornerstone of GIA’s mission. I can think of no better way to honor Mr.
Crowningshield’s legacy.”


The International Mineralogical Association accepted
crowningshieldite as a mineral on September 18, the GIA added.


Main Image: Diamond with crowningshieldite. Right: G. Robert Crowningshield. (GIA)