Paraiba or Not? Cu-bearing Tourmaline with a Distinct Fe Concentration
Paraiba or Not? Cu-bearing Tourmaline with a Distinct Fe Concentration. Published in Journal of Gemmology, 2022, 38 (1), 20-22.
SSEF turns 50 – enter quiz and win prizes!
SSEF turns 50 in 2022! The non profit Schweizerische Stiftung für Edelsteinforschung was founded on August 22nd 1972 by Swiss trade organisations. Test your knowledge (all the answers can be found on our website) with 10 questions about SSEF and gems, and enter the draw to win three fantastic prizes. First pri
Damage caused to gemstones by lasers during jewellery repair
Damage caused to gemstones by lasers during jewellery repair. Journal of the Gemm. Ass. of Hong Kong, Vol. 43, 23-27.
SSEF conducts analysis of cobalt-blue spinel from a newly reported source in Tanzania
For several months already a supply of blue cobalt-bearing spinel has been appearing in the gem trade, including some stones of remarkable size -up to 40 carats- and quality. According to information from reliable sources, the source of the new find is a deposit located about 20 kilometres south-east of Mahenge
News from the SSEF (2022)
Presentation by Dr. Michael S. Krzemnicki at the Swiss Gemmological Society SGG conference in 2022.
Natural pearl necklace with one imitation pearl
Our testing not only revealed the presence of 40 natural pearls of a quite remarkable diameter (8-11 mm), but in addition one imitation pearl consisting of a plastic bead covered by a ‘lacquer’ coating that seeks to mimic a pearly lustre.
Heated spinel from Tajikistan
The spinels were nearly free of any inclusions except for a few tiny colourless forsterite inclusions. In combination with trace element analyses, the origin of these spinels could be unambiguously attributed to the famous spinel mines near Kuh-i-Lal, located in the Pamir mountains in southern Tajikistan, close
The science of gem testing at SSEF: a fascinating tale
Gemmology is a science with its foundations more than a hundred years ago, specifically driven by the emergence of synthetic stones and cultured pearls in the gem trade in the early 20th century.
Visit to the Mong Hsu ruby deposit in Myanmar (Burma)
Mong Hsu is one of the reputed ruby deposits in Myanmar (Burma). It is located about 250km southeast of Mogok, in the Shan State, in northeastern Myanmar.
Diamond fraud uncovered
As in the past, the SSEF is regularly asked by the Swiss police authorities to act as a gemmological adviser in criminal cases. Usually, these are fraud cases, involving undeclared or mislabeled gemstones or their imitations. In a recent case with about 20 stones submitted by the police, we not only found diamo