Press Release: 29. April 2004

SSEF Swiss Gemmological Institute offers a new method for beryllium detection and chemical fingerprinting of gemstones

With the appearance of Be diffused corundum in the trade it became obvious that gemmological laboratories need up-to-date analytical technologies in order to analyse even light chemical constituents in gemstones down to low trace concentrations. So far, the beryllium detection was achieved with micro mass spectrometry (e.g. LA-ICP-MS or SIMS), a technology which is costly and not always in the reach of gemmological laboratories. In collaboration with research bodies, SSEF developed a new method, based on laser induced optical emission spectroscopy, which offers a feasible and affordable alternative for trace elemental analysis of gemstones. Laser induced breakdown spectroscopy (LIBS) is now used successfully by SSEF Swiss Gemmological Institute, especially for the identification of beryllium (Be) diffused corundum. As already announced in March 2004 in Jewellery News Asia, SSEF is able to detect Be concentrations in gemstones down to a few ppm at a very competitive rate.

Our specially designed method uses a focused pulse of a Nd:YAG laser. The gemstone is kept on a sample stage which allows a perfect spot focusing on the stone. The single laser pulse transforms some micrograms of the gemstone sample into plasma. The light emission is diffracted and recorded by a multichannel analyser and the line spectrum can be used for qualitative and quantitative analysis. Almost all chemical elements are detectable, and the method allows a precise chemical fingerprinting of gem materials. A quantitative analysis is possible when reference samples are used whose contents have been determined previously by LA ICPMS or SIMS. The new method is slightly destructive in that a tiny burning spot remains after a laser shot. The system used by SSEF is specially designed for the use in a gemmological laboratory. So far, SSEF has tested a large range of corundum samples and will start the new beryllium detection service in a very short time

We will offer to the gemstone trade and to gemmological laboratories:

• GemLIBS training
• GemLIBS instrument (package including GemLIBS standards, GemLIBS sample holder, GemLIBS sample stage, GemLIBS training)
• GemLIBS standard materials for quantification of LIBS spectra

For any details, please contact SSEF at gemlab@ssef.ch 

More informations here (pdf, 1.16 MB)

Detailed information about LIBS (pdf, 258 kB)