DNA Fingerprinting and age dating of historic natural pearls: a combined approach
DNA Fingerprinting and age dating of historic natural pearls: a combined approach. IGC 2023 Proceedings, 157-158.
SSEF at GemGenève (02-05 November 2023, Booth A71)
SSEF is honoured to take part in the upcoming edition of the GemGenève show at Palexpo in Geneva. We will be offering coloured gemstone express testing services at our booth A71. SSEFGemGenève Booth A7102-05 November 2023 (November 1st is setup day, goods can be submitted from 10am onwards)Tel: +41 79 219 72
Effects of Gamma Irradiation on Ruby and Pink Sapphire and Potential Detection Methods in Gem Labs
Keywords: Ruby, Pink sapphire, Gamma irradiation, UV-VIS, Raman, R-Line
Further Characterisation of Native Copper Inclusions in Cu-Bearing Tourmaline
Further Characterisation of Native Copper Inclusions in Cu-Bearing Tourmaline. The Journal of Gemmology, 38(5), 427-429.
SSEF on-site testing in Hong Kong, 14 – 24 September 2023
We will be in Hong Kong 14 – 24 September offering our on-site testing services, during the upcoming Hong Kong Jewellery and Gem Fairs. Equipped with our mobile instruments and spectrometers, we will be testing coloured gemstones (no diamonds or pearls) at the Asia World Expo (AWE, 18 – 22 September 2023, b
Irradiation Treatment in Rubies and other Corundum Varieties: Update about Ongoing Research at SSEF on this Issue
Irradiation of corundum varieties to change and enhance their colour is known since many decades but remains a difficult and challenging issue until today, as no gemmological method is currently known which would allow an unambiguous detection of this type of treatment.
Led light boxes for standardized lighting of coloured stones and diamonds
In the past, coloured gemstones and diamonds were often examined in natural daylight, but reproducing such specific lighting conditions was challenging. Some impractical methods had been suggested, like grading only during specific hours or facing northward, especially during cloudy weather.
At the frontier of research: irradiation experiments on corundum
As is known in the gem trade, the colour of certain gems may be caused or influenced by the presence of colour centres (a type of defect in the crystal structure that can absorb light and thus result in colour, that can be present both in stable or unstable form).
Purple love
It is always a pleasure for our team to analyse gemstones which are not so common, or sometimes even very rare, but which may compete in beauty and quality (but often not in hardness) with the most prestigious classic gemstones.
Dark purple chrysoberyl
Since about three years, we see at SSEF occasionally chrysoberyl samples of very dark purplish to purplish brown colour, sometimes of quite impressive size (>10 ct). Based on chemical composition, these chrysoberyls show distinct concentration of chromium, but no evident change of colour, thus do not fit the cr