23. Oct IGC 2023 Colour change Paraiba tourmaline from Brazil By Claudio C. Milisenda, Stefan Müller Download Pdf Tourmaline
23. Oct IGC 2023 Violet Diamonds from Argyle: New Insights into the Cause of their Unique Color Until its recent closure, the Argyle mine in Australia has been the only source of uniquely colored Read More Elodie
23. Oct IGC 2023 Color enhancement in yellow sapphire Natural yellow sapphire is colored by one or the combination of two different chromophores, Fe3+ and Read More Elodie
23. Oct IGC 2023 Purple to bluish grey chalcedony from Ethiopia In the past 15 years, Ethiopia has repeatedly gained attention for a variety of new gem finds. In 20 Read More Elodie