| Articles |
|
|
|
|
Revelation of Causes of Colour Change in Beryllium-Treated Sapphires |
| Pichet Limsuwan1;Siwaporn Meejoo2;Asanee Somdee2;Kheamrutai Thamaphat1;Treedej Kittiauchawal1;Atitaya Siripinyanond2;Jurek Krzystck3 |
| 1Department of Physics, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand2Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand3Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Drive, Tallahassee, Florida 32310, U.S.A. |
|
| Cite this article: |
|
Pichet Limsuwan, Siwaporn Meejoo, Asanee Somdee et al 2008 Chin. Phys. Lett. 25 1976-1979 |
|
|
|
|
Abstract Blue sapphires are treated with Be in oxidizing atmosphere to change the blue colour into yellow. Untreated and Be-treated samples are examined using laser ablation inductively coupled-plasma-mass spectrometry (LA-ICP-MS), electron spin resonance (ESR) and ultraviolet--visible (UV--vis) spectroscopy. The results show that the yellow colouration in Be-heated blue sapphires is not due to Be diffusion from the surface of sapphire. Be behaves as a sole catalyst in this process. We find that the charge transfer between the ferrous (Fe2+) and ferric (Fe3+) is the reason of the colour change. The above conclusions are confirmed by ESR measurements to determine the connections between the Fe3+ ions before and after Be-treated heat treatments.
|
| Keywords:
07.60.Rd
52.25.Os
82.80.Ms
87.64.Kh
|
|
|
Received: 07 March 2008
Published: 31 May 2008
|
|
| PACS: |
07.60.Rd
|
(Visible and ultraviolet spectrometers)
|
| |
52.25.Os
|
(Emission, absorption, and scattering of electromagnetic radiation ?)
|
| |
82.80.Ms
|
(Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI))
|
| |
87.64.kh
|
(EPR)
|
|
|
|
|
|
[1] Hughes R W 1990 Corundum (London: Butterworth-Heinemann)
[2] Themelis T 1992 The Heat Treatment of Ruby andSapphire (USA: Gemlab Inc)
[3] Nassau K 1994 Gemstone Enhancement: History, Science,and State of the Art (Oxford: Butterworth-Heinemann)
[4] Udomkan N et al %, Limsuwan P, Winotai P and Meejoo S2005 Int. J. Mod. Phys. B 19 3273
[5] Arnond V P, H\"aer T, Wathanakul P and Atichat W 2004 J. Gemm. 29 77
[6] Coldham T 2002 Australian Gemologist 22 288
[7] Emmett J L et al %, Scarratt K, Mc Clure S F, Moses T,%Douthit T R, Hughes R W, Novak S, Shigley J E, Wang W, Bordelon O%and Kane R E2003 Gems Gemology 39 84
[8] Novak S W et al %, Magee C W, Moses T and Wang W2004 Appl. Sur. Sci. 231-232 917
[9] Hassan A K et al %, Pardi L A, Krzystek J, Sienkiewicz A,%Goy P, Rohrer M and Brunel L C2000 J. Magn. Reson. 142300 |
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
