Diamonds
GSL assesses and certifies a large amount of white and coloured diamond material every week, with services extending from verbal assessment to full certification. All diamonds graded by GSL carry a unique reference number, allowing the client access to the full grading specifications of a stone. All diamonds are first checked for possible HPHT treatment before the final grades are assigned to the stone. In the case of coloured diamonds, GSL can also potentially identify the stones country of origin.
