Why is a Diamond of Type IIb blue to greyish blue?
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.
ASDI (Automated Spectral Diamond Inspection)
by J.-P. Chalain, first published in Facette 21 (F […]
Undisclosed natural diamonds mixed in a parcel of synthetic diamond
by J.-P. Chalain, first published in Facette 22 (F […]
CVD Synthetic Diamonds and Testing at SSEF
by J.-P. Chalain, first published in Facette 20 (Januar […]
The Detection of HPHT-treatment of Diamonds at SSEF: 20 Years later
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.
Study of a recut HPHT synthetic diamond: Colour VS size VS SWUV transmission (2019)
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
A Preliminary SIMS Study Using Carbon Isotopes to Separ […]
Diamond testers with a limited performance
Diamond testers with a limited performance. Published i […]
L’identification du traitement HPHT au SSEF (2015)
Presentation by Jean-Pierre Chalain at 2015 Swiss Gemmological Society conference on HPHT treatment detection at SSEF
Contributions de la gemmologie de laboratoire à l’identification du traitement HPHT du diamant
Contributions de la gemmologie de laboratoire à l’ […]