Change Principle of Diamonds Before and After Heat Treatment

According to Science Daily, researchers sponsored by DE Beers use SuperSTEM electron microscope from Engineering and Physical Sciences Research Council (EPSRC) to study why some of diamonds are in brown, and the change principle of diamonds after heat treatment.

Dr. Iain Godfrey views the study as part of his PhD at University of Manchester. He has tested the electronic structure of diamonds before and after heat treatment, and analyzed the atomic vacancy defects inside the diamond. Experimental results have confirmed that the diamonds' void fraction is related with the color of  diamonds.

Dr. Godfrey says: "The research becomes feasible with the help of SuperSTEM, and SuperSTEM is particularly sensitive scanning transmission electron microscope. We find that brown diamonds have slight defects, but the colorless diamonds do not have such defects."

He adds: "Defects can change the light-absorbing wavelength of diamonds, which leads to the essential difference of two kinds of color diamonds."

David Fisher, the chief scientist of DE Beers says: "understanding what happened inside diamonds will help us to distinguish whether it is the heat treatment technology of diamond. The study of atomic level can help us to ensure the consumer confidence for diamonds, and ensure that all links are transparent."