Grading reports produced by IGI will now offer a "light performance score" for round brilliant cut diamonds.
They'll provide an overall score - low, moderate,...
The International Gemological Institute (IGI) has introduced Light Performance Grading Reports showcasing round brilliant-cut diamonds with exceptional optical qualities. The IGI Light Performance grading...
The 101.29-carat Allnatt diamond, described as one of the world's most significant fancy vivid yellow stones, is to be auctioned at Sotheby's Geneva, with...