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.
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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EGUsphere, https://doi.org/10.5194/egusphere-2025-1810, https://doi.org/10.5194/egusphere-2025-1810, 2025
This preprint is open for discussion and under review for Geochronology (GChron).
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Chemical abrasion (CA) is a two step method for reducing Pb loss where zircon is annealed then partially dissolved. We use SIMS to find closed and open system zircon domains in zircon that has been CA, annealed only, or untreated. Raman mapping shows to identify lattice damage in SIMS spots. Atom Probe (APT) results from both the discordant spots and concordant ones are all homogenous and identical. Thus APT cannot distinguish discordant and concordant zircon.
Inna Lykova, Ralph Rowe, Glenn Poirier, Gerald Giester, Kelsie Ojaste, and Henrik Friis
Eur. J. Mineral., 35, 133–142, https://doi.org/10.5194/ejm-35-133-2023, https://doi.org/10.5194/ejm-35-133-2023, 2023
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A new mineral group – the mckelveyite group – consisting of seven carbonate minerals was established. One of the seven members, donnayite-(Y), was re-investigated and its belonging to the mckelveyite group was confirmed.
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Solid Earth, 5, 1099–1122, https://doi.org/10.5194/se-5-1099-2014, https://doi.org/10.5194/se-5-1099-2014, 2014
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Three types of lattice distortion patterns in deformed zircon are detected: (I) gradual bending of the crystal lattice without subgrain boundaries, (II) local gradual bending of the lattice with formation of semicircular subgrain boundaries, and (III) strain-free subgrains separated by subgrain boundaries. The difference is controlled by strain rate and differential stress. Activation of energetically preferable slip systems is facilitated by decoupling from matrix and/or by soft host mineral.
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Subject area: Crustal structure and composition | Editorial team: Geochemistry, mineralogy, petrology, and volcanology | Discipline: Mineralogy
Spectral characterisation of hydrothermal alteration associated with sediment-hosted Cu–Ag mineralisation in the central European Kupferschiefer
The acid sulfate zone and the mineral alteration styles of the Roman Puteoli (Neapolitan area, Italy): clues on fluid fracturing progression at the Campi Flegrei volcano
Generating porosity during olivine carbonation via dissolution channels and expansion cracks
Léa Géring, Moritz Kirsch, Samuel Thiele, Andréa De Lima Ribeiro, Richard Gloaguen, and Jens Gutzmer
Solid Earth, 14, 463–484, https://doi.org/10.5194/se-14-463-2023, https://doi.org/10.5194/se-14-463-2023, 2023
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We apply multi-range hyperspectral imaging on drill core material from a Kupferschiefer-type Cu–Ag deposit in Germany, mapping minerals such as iron oxides, kaolinite, sulfate, and carbonates at millimetre resolution and in a rapid, cost-efficient, and continuous manner to track hydrothermal fluid flow paths and vectors towards base metal deposits in sedimentary basins.
Monica Piochi, Angela Mormone, Harald Strauss, and Giuseppina Balassone
Solid Earth, 10, 1809–1831, https://doi.org/10.5194/se-10-1809-2019, https://doi.org/10.5194/se-10-1809-2019, 2019
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The Campi Flegrei volcano in Italy displays hot fumarolic solfataras famous since Roman times. We use the solfataric mineralizations to investigate the local setting, evolution and geohazards. These provide information on hydrothermal activities that have been stable over the past 20 years. They reflect extreme conditions associated with the fluid overflow from subsurface and surface waters through a fracturing conduit. The solfataras are toxic and represent an extreme environment for life.
Tiange Xing, Wenlu Zhu, Florian Fusseis, and Harrison Lisabeth
Solid Earth, 9, 879–896, https://doi.org/10.5194/se-9-879-2018, https://doi.org/10.5194/se-9-879-2018, 2018
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The olivine carbonation reaction is volume increasing and could prevent further reaction by clogging the fluid pathways. This contradicts the observed fully carbonated outcrops in nature, but the mechanism behind this self-sustainability is poorly understood. Our study reveals that the stretching-induced fracturing and the dissolution channelization are mechanisms that could contribute to the sustainability of carbonation reactions. This study provides new insights on the olivine carbonation.
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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...