GJ Town India

  Distinct colorless and pink bicolor rough diamond   The GIA laboratory in Botswana recently examined an extraordinary pink-and-colorless bicolor rough diamond. Reportedly from the Karowe mine, the source of several notable diamonds, including the 2,488 ct Motswedi diamond, also examined by GIA, the 37.41 ct rough diamond has distinct colorless and pink sections, possibly indicating that the diamond formed at two different times.  “It is generally understood that pink color in diamonds results from significant stress causing a change in the diamond’s crystal structure known as plastic deformation,” said Dr. Sally Eaton-Magaña, senior manager of diamond identification at GIA in Carlsbad, California. “The pink section likely was initially colorless and then plastically deformed, perhaps by a mountain-forming event millions of years ago, resulting in its pink color, with the colorless section forming at a later time.”    An article analyzing the bicolor diamon...

  Motswedi, a water spring or source in Setswana language of Botswana    In July 2025, staff from the Gemological Institute of America (GIA), including GIA Executive Vice President and Chief Research and Laboratory Officer Tom Moses and Vice President of Research and Development Dr. Wuyi Wang, examined a rough diamond weighing 2,488.32 carats—nearly 1.10 pounds (0.498 kilograms)—at the Institute’s laboratory in Gaborone, Botswana.     “This is undoubtedly a diamond of great historical importance,” said Tom Moses. “I have been fortunate to examine many significant, large and very rare diamonds, but I have never seen a gem quality diamond of nearly this size.”     Recovered in August 2024 by the Lucara Diamond Corporation at the Karowe diamond mine in Botswana, this diamond is second in size only to the legendary 3,106-carat Cullinan diamond, which was found in South Africa 120 years ago.  Weighing 2,492 carats at recovery and generally ...

  This is in response to the recent logistics challenges   In response to logistics challenges related to recently announced tariffs affecting global shipments of gemstones, GIA (Gemological Institute of America) will temporarily expand services offered by the GIA Laboratory DMCC and the GIA Hong Kong laboratory.   D-to-Z diamonds, rough or polished, up to 9.99 cts may be submitted to the GIA laboratories in Dubai and Hong Kong. D-to-Z diamonds, rough or polished, 10 cts and above and fancy color diamonds may be submitted to the GIA laboratory in Hong Kong until further notice.    D-to-Z diamonds, rough or polished, up to 3.99 cts may continue to be submitted to the GIA laboratories in Bangkok, Dubai, Gaborone, Hong Kong, Johannesburg, Mumbai, Surat and Tokyo.  Rough diamond submissions are subject to the Kimberley Process Certification rules in each country; rough diamonds cannot be shipped to the GIA laboratory in Dubai.   The GIA la...