Comparing the absorption spectra of type IIa and type IIb diamonds greatly helps to better understand why a diamond of type IIb is blue to greyish blue.
by J.-P. Chalain, first published in Facette 21 (February 2014) In 2013, numerous trade-press articles and gemmological laboratory alerts warned the diamond industry about the presence of synthetic diamonds mixed together with, or presented as, natural diamonds. These announcements pointed out that not onl
by J.-P. Chalain, first published in Facette 22 (February 2016) In 2016, our Diamond Department acquired a parcel of small colourless synthetic diamonds produced in Europe by the HPHT method. The complete study of these series of melee size synthetic diamonds (SSEF Research project 80602) is part of our co
by J.-P. Chalain, first published in Facette 20 (January 2013) Synthetic diamonds have been present in the gem trade for over two decades. Recent financial investments and advances in technology have now made them more affordable both in terms of price and availability. The SSEF has been following synthetic di
In 2000, SSEF announced that it was able to identify the HPHT treatment of type II diamonds. About 20 years later, this article summarizes how we were able to achieve this breakthrough and which people from the trade and other research institutions were involved in this important step.
The diamond trade today is seriously concerned about synthetic diamonds mixed in with parcels of natural diamonds; however, we also propose here that the opposite situation of natural diamonds mixed in with batches of synthetic diamonds is also something to be concerned about and will in the near future be a (
Presentation by Jean-Pierre Chalain at the International Gemmological Conference (IGC) in August 2019.
A Preliminary SIMS Study Using Carbon Isotopes to Separate Natural from Synthetic Diamonds. Published in Journal of Gemmology, 2018, 36, 1, 38-43. Author(s) : H.A.O. Wang, L.E. Cartier, L.P. Baumgartner, A.-S. Bouvier, F. Begué, J.-P. Chalain, M.S. Krzemnicki
Presentation by Jean-Pierre Chalain at 2015 Swiss Gemmological Society conference on HPHT treatment detection at SSEF