Spectrofluorometer: New instrument at SSEF
We have acquired a new instrument at SSEF: a JASCO FP-8550 spectrofluorometer. A spectrofluorometer is a device that can measure fluorescence excitation and emission spectra.
Phosphorescence spectrometry of diamonds
The JASCO FP-8550 spectrofluorometer. The instrument has a variety of applications. Here, we report on the phosphorescence lifetime study of a 0.705 ct, round, brilliant-cut, colourless (H/VS1), natural diamond (reference NBMJ).
Gemmological study of the medieval Königsfelder diptychon
In 1298 AD, the king of Hungary Andreas II presented to his wife Queen Agnes a stone-set wooden altar piece as a royal wedding present. This small medieval artwork, known today as the Königsfelder diptychon, was originally made in Venice.
Gemtof successfully passed G-Chron 2019 proficiency test on zircon U-Pb dating
The quality and consistency of analytical data is important for gem labs in order to provide replicable results to gemmologists over a long period of time. In addition, the accuracy compared to internationally recognised standards allows us to perform inter-lab comparisons or track instrument performance and tr
A new led daylight source for diamond colour grading
In 2020, a novel light source for the colour grading of diamonds was developed in a collaboration between SSEF and the Department of Physics, University of Basel (see Figure 1). In contrast to many of the models on the market, the new light source uses state-of-the-art LED (Light Emitting Diode) lights instead
Zircon inclusions in unheated pink sapphires from Ilakaka, Madagascar: A Raman spectroscopic study
Zircon inclusions in unheated pink sapphires from Ilaka […]
New statistical methods for analysis of gemstones
Based on real case studies on sapphire and emerald specimens, we here present how a simultaneous multi-element approach assists origin determination. Instead of pre-defining a list of isotopes in advance, routine analysis of blue sapphires using LA-ICP-TOF-MS detects rarely occurring trace elements such as bery
SSEF introduces machine learning algorithm for data visualization
by Dr. H.A.O. Wang, first published in Facette 21 (June […]
Sub-surface laser inscription and marking of gemstones
by Dr. L.E. Cartier, first published in Facette 26 (May […]
ASDI (Automated Spectral Diamond Inspection)
by J.-P. Chalain, first published in Facette 21 (F […]