first published in Facette 21 (February 2014) Vanadium-bearing chrysoberyl of light green to saturated green colour has been known in the trade since the mid-1990s. Originally first described from Tunduru in southern Tanzania (Johnson & Koivula 1996, Pfenniger 2000), similar attractive “mint green” chr
Paraiba Research Update: An elemental Analysis of Paraiba Tourmaline from Brazil
At the SSEF, origin determination of Paraiba tourmalines is based on years of experience researching collection samples from SSEF and Prof. Hänni collections, donated and loaned samples from clients, as well as knowledge from scientific literature. However, the mining area and depth of the material have been i
Blue cobalt spinel from Vietnam
by Dr. M.S. Krzemnicki, first published in Facette 21 (February 2014) In 2013, Ms. Carina Hanser from the University Freiburg im Breisgau in Germany successfully completed her bachelor thesis on cobalt-spinel from Vietnam. Under the supervision of Dr Krzemnicki, Prof de Capitani (University Basel) and Prof
Jade, Stone of “Gods”: Terms, Concepts & Certification
Jade, for thousands of years a mythical stone appreciated in the Far East and in the high cultures of Native Americans, is rising high at present as it is sought after at auctions in Hong Kong and elsewhere. However, the term “jade” is quite vaguely defined. Different concepts try to describe the term based
Multi-Element Correlation Analysis of Cu-bearing Tourmaline using LA-ICP-Time-Of-Flight-MS
Multi-Element Correlation Analysis of Cu-bearing Tourmaline using LA-ICP-Time-Of-Flight-MS. EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-16170, https://doi.org/10.5194/egusphere-egu21-16170, 2021.
U–Pb Dating of Zircon and Zirconolite Inclusions in Marble-Hosted Gem-Quality Ruby and Spinel from Mogok, Myanmar
U–Pb Dating of Zircon and Zirconolite Inclusions in Marble-Hosted Gem-Quality Ruby and Spinel from Mogok, Myanmar. Published in Minerals, 2020, 10, 195. Link to article
GemTOF Analyses of Sapphires from Madagascar and Kashmir
In the beginning of 2017, gem testing laboratories started to receive cut stones from a new area for gem analysis and issuing reports. As stated in a trade-alert by SSEF in early 2017, some of this new sapphire material may resemble internal features of Kashmir blue sapphires, therefore careful microscopic inve
Multi-Element Analysis of Gemstones For Country of Origin Determination (2019)
Presentation at IGC 2019 in Nantes (France) by Dr. Hao Wang.
Gemstones of the Garnet Group – about mixed crystals and solid solution
Gemstones of the Garnet Group – about mixed crystals and solid solution. Published in Journal of the Gemmological Association of Hong Kong GAHK, 2019, Volume XL, 36-49.
A Gemmological Approach to Distinguishing Natural from Synthetic Rubies: LA-ICP-TOF mass spectrometry provides new insights (2019)
Presentation at ECMS 2019 in Prague (Czech Republic) by Dr. Tashia J. Dzikowski-Hutter.