Characterization of gem stones (rubies and sapphires) by energy-dispersive x-ray fluorescence spectrometry

✍ Scribed by D. Joseph; M. Lal; P. S. Shinde; B. D. Padalia

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 70 KB
• Volume: 29
• Category: Article
• ISSN: 0049-8246
• DOI: 10.1002/(sici)1097-4539(200003/04)29:2<147::aid-xrs370>3.0.co;2-k

✦ Synopsis

Trace elemental analyses of rubies and sapphires from different countries of origin were carried out by the EDXRF technique. It was found that K, Ti, Cr, Fe, Cu, Zn, Sr and Ba are generally present in natural rubies and Cr, Ni, Cu and Zr in synthetic ruby. The synthetic ruby shows a clean spectrum devoid of iron whereas the presence of Fe is seen in all the naturally occurring rubies irrespective of the country of origin. The elements present in Indian sapphires are Ca, Fe, Sr and Mo and their estimated concentrations are 0.10, 0.18, 0.029 and 0.006%, respectively. Further, preliminary XRD studies showed patterns of synthetic rubies different from those of the naturally occurring rubies. The results demonstrate that EDXRF can be used to distinguish between natural and synthetic rubies.