Emeralds and the Saga of Cleaning and Filling Fissures
There is a long established tradition in the trade to fill open fissures in emeralds with colourless fillers, such as oil, wax and (artificial) resins, to reduce their visibility. Disclosure of such treatments is mandatory (CIBJO), including a quantification of the filler substance, as this may have a direct im
Research on Golden Cultured Pearls
In February 2016 Dr. Laurent Cartier had the opportunity of visiting Jewelmer pearl farms near Palawan Island in the Philippines and observing the different culturing techniques required to harvest golden South Sea pearls.
Study of opalised Dinosaur Vertebra
Recently, the Swiss Gemmological Institute SSEF received an exceptional opalised dinosaur vertebra for study. This specimen was reportedly from Lightning Ridge (New South Wales in Australia) – a world famous source of dark opals and opalised plant and animal fossils - and was already photographed by Elizabeth
The Challenge: Identification of a Ramaura Synthetic Ruby
by Dr. Michael S. Krzemnicki, first published in F […]
Spinel from Mahenge (Tanzania) and its Heat Treatment
first published in Facette 22 (February 2016) In 2 […]
Undisclosed natural diamonds mixed in a parcel of synthetic diamond
by J.-P. Chalain, first published in Facette 22 (F […]
Colourless Diopside from Kenya and Canada
first published in Facette 22 (February 2016) Diopside, […]
Zircon Showing Asterism
first published in Facette 22 (February 2016) Martin St […]
Paraiba Tourmaline Intergrown with Lepidolite Mica
by Dr. M.S. Krzemnicki, first published in Facette 20 ( […]