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.
Fissure-filling in Paraiba Tourmaline
As with any gemstone with fissures, it is of no surprise that some Brazilian Paraiba Tourmaline is filled with a colourless foreign substance (mostly artificial resin) to modify and enhance its transparency and thus apparent beauty.
Fake Tridacna Pearls
Fake pearls are beads (of whatever shape) which have been cut entirely from shell material. A perfect source for the production of such fake pearls is the Tridacna clam, amongst the largest living bivalve mollusc with a massive and thick shell of up to 110 cm diameter, mainly living along shallow coastal water
Neutron and X-Ray Tomography of Emeralds
Since two years, the SSEF has been working with the Laboratory for Neutron Scattering and Imaging at the Paul Scherrer Institute (PSI) using their ICON beamline (cold neutron imaging) at the SINQ spallation source. The aim of these research projects in collaboration with Dr. Lehmann and Dr. Mannes is to analyse
Rarities and Collector Stones Tested at SSEF
The daily routine at SSEF usually consists of testing rubies, sapphires, emeralds, pearls and diamonds. Although sometimes challenging and interesting, especially taking into account the quality and the documented historical provenance of some of these gems and jewellery items, it is also always of great intere
Purple Mozambique Garnet
In early 2016, attractive bright purple garnets arrived at SSEF in Bangkok, Basel and Hong Kong. Based on client information, they are from a new mine, Padagaga in the Chimoio area in Mozambique, which was discovered recently.
Rubies with Oil in Fissures
Over the past few years, the SSEF has repeatedly seen gemstones (apart from emeralds) which contained fissures filled with oil or other fillers. These include rubies, sapphires, spinels, tourmalines, garnets and even rarities such as pezzottaite.
The historic ‘Sleeping Lion Pearl’, a natural Blister and not a Pearl
Recently, the Swiss Gemmological Institute SSEF had the opportunity to investigate an impressive natural nacreous formation with documented provenance dating back to the late 18th century, named the ‘Sleeping Lion Pearl’ due to its baroque shape that is reminiscent of a lion.
How Diamonds Salted Inside Batches of Synthetic Diamonds Creates Confusion
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 (
Ethiopia: New Source for Sapphires and Emeralds
In 2016 the first emeralds appeared in the gem trade which reportedly came from new deposits discovered near the town of Shakiso in southern Ethiopia. Soon after, some of these stones partly of high quality were submitted to the SSEF and we were able to collect microscopic and analytical data and to integrate a