Articles | Volume 16, issue 1
https://doi.org/10.5194/se-16-81-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-16-81-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Jan 2025
Research article |
| 24 Jan 2025
| 24 Jan 2025
Luminescence and a new approach for detecting heat treatment of geuda sapphire
Teerarat Pluthametwisute
Hub of Talents in Gem and Jewelry Industries, Department of Geology, Faculty of Science, Chulalongkorn University, 10330 Bangkok, Thailand
Institut für Mineralogie und Kristallographie, Universität Wien, 1090 Vienna, Austria
Lutz Nasdala
Institut für Mineralogie und Kristallographie, Universität Wien, 1090 Vienna, Austria
Chutimun Chanmuang N.
Institut für Mineralogie und Kristallographie, Universität Wien, 1090 Vienna, Austria
Manfred Wildner
Institut für Mineralogie und Kristallographie, Universität Wien, 1090 Vienna, Austria
Eugen Libowitzky
Institut für Mineralogie und Kristallographie, Universität Wien, 1090 Vienna, Austria
Gerald Giester
Institut für Mineralogie und Kristallographie, Universität Wien, 1090 Vienna, Austria
E. Gamini Zoysa
Mincraft Co., 10370 Mount Lavinia, Sri Lanka
Chanenkant Jakkawanvibul
The Gem and Jewelry Institute of Thailand (Public Organization), 10500 Bangkok, Thailand
Waratchanok Suwanmanee
The Gem and Jewelry Institute of Thailand (Public Organization), 10500 Bangkok, Thailand
Tasnara Sripoonjan
G-ID Laboratories, Bangkok, 10120, Thailand
Thanyaporn Tengchaisri
Science and Technology Park (STeP), Chiang Mai University, 50200 Chiang Mai, Thailand
Bhuwadol Wanthanachaisaeng
The Gem and Jewelry Institute of Thailand (Public Organization), 10500 Bangkok, Thailand
Chakkaphan Sutthirat
CORRESPONDING AUTHOR
Hub of Talents in Gem and Jewelry Industries, Department of Geology, Faculty of Science, Chulalongkorn University, 10330 Bangkok, Thailand
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Short summary
For decades, gemologists have struggled to detect heat-treated sapphire. High-technology instruments like Fourier-transform infrared (FTIR) spectrometers are costly. As a result, luminescence under shortwave ultraviolet (SWUV) light and longwave ultraviolet (LWUV) light provides a cheaper and more practical technique for identifying heat-treated sapphire. This work highlights that blue luminescence under SWUV light could indicate heated sapphire, whereas purplish-red may also be helpful.
For decades, gemologists have struggled to detect heat-treated sapphire. High-technology...
