Platon N. Gamaletsos

Platon N. Gamaletsos
Technical University of Crete | TUC · School of Mineral Resources Engineering

Doctor of Philosophy
(Nano)-mineralogy of various primary & secondary mineral resources (e.g., ore deposits, byproducts, waste streams, etc.)

About

70
Publications
19,416
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Introduction
Platon N. Gamaletsos (a.k.a. Platon N. Gkamaletsos; ResearcherID: N-2459-2018 & ORCID: 0000000211719032) holds a PhD of Geological & Geoenvironmental Sciences. He is a mineralogist specialized in various mineral resources. He focuses on the investigation of ore deposits, metallurgical residues & mineral waste streams using -among others- Synchrotron-based spectroscopy (micro-XAFS), and e-microscopy techniques in micro-/nano-scale (SEM, TEM). He is a member of the Marie Curie Alumni Association.
Additional affiliations
July 2020 - present
Technical University of Crete
Position
  • Professor (Assistant)
Description
  • Assistant Professor of Applied Mineralogy-Petrology, School of Mineral Resources Engineering, Technical University of Crete (Chania, Crete Island, Greece).
July 2020 - October 2021
National Center for Scientific Research Demokritos
Position
  • Professor
February 2020 - October 2021
KU Leuven
Position
  • Research Associate
Description
  • Visiting Research Associate (external co-worker at KU Leuven) at Prof. Dr. Yiannis Pontikes’ group of Sustainable Metals Processing and Recycling Unit
Education
January 2006 - September 2014
National and Kapodistrian University of Athens
Field of study
  • Mineralogy & Geochemistry of Ore Deposits and Metallurgical Residues

Publications

Publications (70)
Article
Full-text available
We present new data about the chemical and structural characteristics of bauxite residue (BR) from Greek Al industry, using a combination of microscopic, analytical, and spectroscopic techniques. SEM-EDS indicated a homogeneous dominant “Al-Fe-Ca-Ti-Si-Na-Cr matrix”, appearing at the microscale. The bulk chemical analyses showed considerable levels...
Conference Paper
In some gold deposits, gold exists as invisible form in pyrite and/or arsenopyrite and its concentration is extremely low. Such gold is not recovered readily from ore materials. The identification of the gold form and distribution may provide some insight into the recovery of gold. Here we use various microscopic techniques such as electron microsc...
Article
Full-text available
To tackle the challenge of bauxite residue (BR), generated during the alumina production, as well as to recover some of its metal content, three combinatory H2-based processes were utilized. Firstly, Greek BR was mixed with NaOH to produce water soluble Na-aluminates and was roasted under pure H2 gas in order to reduce the Fe+3 content. Then the fi...
Article
The understanding of ophiolites as hosts to economic–scale chromitite ore deposits requires the integration of research relating their geochemical metallogenesis with studies of the mode and nature of their lithospheric-scale deformation. The Neotethyan Vourinos ophiolite in Northern Greece represents a well-preserved ophiolite complete with sheete...
Article
Full-text available
Antimony is a common metalloid occurring in the form of Sb-sulfides and sulfosalts, in various base and noble metal deposits. It is also present in corresponding metallurgical products (concentrates) and, although antimony has been considered a penalty element in the past, recently it has gained interest due to its classification as a critical raw...
Article
Full-text available
Eudialyte-group minerals (EGM) attract global interest as potential resources for high-field-strength elements (e.g. Zr, Nb, Ta, and rare-earth elements), i.e. critical materials for modern technologies. They are particularly valued for their relative enrichment in the most critical lanthanides, i.e. Nd and heavy rare earth elements (Gd-Lu). Howeve...
Article
Allanite-bearing black coastal sands of Kavala (N. Greece) were studied using a combination of single-crystal XRD, EMPA, μ-XRF, bulk ICP-MS, LA-ICP-MS, μ-XANES and γ-ray spectrometry. The sands are rich in REE (ΣREE + Y: 4010 to 10,810 mg/kg), Th (236–1205 mg/kg) and other critical metals such as Nb, Ta and Co. The main REE- and Th-hosts are allani...
Article
Nickeliferous laterite ores from two typical central Greece deposits (Larymna and Evia), currently used in the LARCO GMMSA smelting plant to produce ferronickel, were characterized using a combination of diffraction, microscopic, and analytical techniques. X-ray diffraction patterns of various fractions, with emphasis to the clayey material (<2 μm)...
Article
Full-text available
Published in Journal of Sustainable Metallurgy (https://rdcu.be/8EtH): ___________________________________________________________________________________ More recent data of Greek bauxites from the Parnassos-Ghiona active mines prove that rare earth elements (REEs) occur mainly in the form of authigenic/diagenetic LREE3+ carbonate and phosphate mi...
Conference Paper
The Kassandra mining district contains porphyry Au-Cu and Au-Ag-Pb-Zn-Cu carbonate replacement deposits that are associated with Oligocene-Miocene intrusions emplaced into polydeformed metamorphic basement rocks belonging to the Permo-Carboniferous to Late Jurassic Kerdilion unit and the Ordovician-Silurian Vertiskos unit. Regional extensional tect...
Article
Bauxitic Fe-Ni-laterite ore from the Patitira mine in Lokris area (Greece) contains assemblages of unusual As-bearing goethite-type phases in samples with significant organic matter. The material was initially characterized by bulk ICP-MS and SEM-EDS. Furthermore, the distribution and speciation of As were studied by Synchrotron Radiation (SR) spec...
Article
Full-text available
Chromium-bearing clays occurring at Crommyonia (Soussaki), Greece, are studied in detail. In this area Mesozoic ultramafic ophiolitic rocks were affected by a Pliocene volcanic activity continuing, nowadays, with intense post-volcanic phenomena. Particularly, the Cr-bearing clays were formed at the margins of the ophiolite into highly altered serpe...
Conference Paper
The Nordic region holds some of the world’s largest eudialyte deposits, which contain promising rare earths concentrations. Due to low content of actinides (including thorium / Th) in such rocks, eudialyte would avoid many of the issues of potential radioactive contamination in tailings that bedevil e.g., monazite and xenotime extraction. Here, we...
Conference Paper
In some gold deposits, gold exists as invisible form in pyrite or arsenopyrite. Such gold is not recovered readily from ore materials. The identification of the gold form and distribution may provide some insight into the recovery of gold. Here, we use electron microscopy, NanoSIMS and high energy resolution fluorescence detection X-ray absorption...
Conference Paper
Full-text available
Eudialyte group minerals (EGM) are economically important alkali-zirconosilicates in agpaitic syenites. Alongside c. 12 wt.% ZrO2 and 1-2 wt.% Nb2O5, EGM host c. 1-10 wt.% total rare earth oxides with relatively high proportions of valuable heavy rare earths (c. 35%). The EGM structure can accommodate REE in various sites, mostly inferred to occupy...
Conference Paper
Eudialyte group minerals (EGM) are the focus of commercial interest because they host significant amounts of Zr, Nb and the high value mid-and heavy REE. They are complex alkali-zirconosilicates that crystallize in unusually volatile-rich peralkaline magmas with c.12 wt. % ZrO2 and 1-2 wt.% Nb2O5, and appreciable amounts of (c.1-10 wt.%) total rare...
Conference Paper
Full-text available
Antimony, an emergent global contaminant, that is hydrothermally discharged along with other epithermal metals(-loids) (Au, As, Hg, Ag, Tl, Ag) onto Kolumbo volcano’s shallow (<500 m water depth) crater seabed, is fixed either in pyrite, orpiment-like As-sulfides, and ferrihydrite-like Fe-oxy(hydro)oxides, or forms independent Pb(Zn)- Sb sulfosalts...
Article
Coastal sand samples collected from the northern part of Nisyros volcanic island (Dodecanese, Greece) were investigated for first time for their potential in strategic metals and compared with parental rocks of the island which are Quaternary volcanics with alternating lava flows, pyroclastic layers and lava domes and relevant materials located nea...
Article
Chrome ore deposits comprise less than 1% of the volume of a pervasively serpentinized dunite body (∼3.5 km³) that constitutes the Xerolivado-Skoumtsa Mine of the Vourinos Ophiolite in northwestern Greece. Ores have been examined to aid determination of their geological mode of occurrence, their mineralogy and mineral chemistry (Cr-spinel and olivi...
Article
Synchrotron radiation techniques (μ-XRF and μ-XANES) were applied to the study of organic-rich phosphatized limestones of NW Greece (Epirus). The results revealed uranium accumulation in areas of the material containing, among others, carbonate apatite (francolite) and organic matter. The UL 3-edge of μ-XANES spectra showed that uranium was present...
Article
Full-text available
The treatment of wastewater (initial pH 7.7) from Sindos industrial area of Thessaloniki (Greece) with different proportions (0.1, 0.2, 0.4, 0.8, 1.6, 3.2, and 6.4 g) of Hellenic natural zeolite (HENAZE), resulted in overflowed clear water of pH 7.4–7.3, free of odours and improved by 69–76% for the chemical oxygen demand, 54–70% for nitrate ((Form...
Chapter
Full-text available
This review summarizes the existing data about the geological sources of As in Greece; their variety and the relevant concentrations make Greece a peculiar territory to generalize and better understand the methodology for their assessment. These sources concern As-containing ores in active and abandoned mining areas, geothermal/hydrothermal waters,...
Article
Full-text available
Amorphous orpiment-like As-sulfides (As2S3) are the most common As phases precipitating in hydrothermal systems, yet there is a lack of information regarding their solid-state characterization. Using a combination of optical, SEM-EDS, micro-Raman and XANES/EXAFS applications, we investigated yellow-orange As- and S-rich sediments occurring in the s...
Conference Paper
Full-text available
Representative Greek bauxite and red mud samples were studied by means of X-ray absorption spectroscopy (XAS) in order to investigate the oxidation state and the solid-state structural environment of the Fe atoms.
Thesis
Karst-type bauxite deposits have been exploited in central Greece, in the area of legendary Parnassos Mountain near the Oracle of Delphi, since 20’s. The existence of bauxite in Parnassos-Ghiona was announced around 1922, giving possibilities of developing an aluminium industry in Greece. The Al-ores are hosted within Mesozoic carbonate formations...
Conference Paper
Full-text available
The commixture of sludge from Sindos industrial area of Thessaloniki with high quality HEU-type natural zeolite (tuff with 86 wt.% clinoptilolite-heulandite) in equal proportions, resulted in odourless and cohesive zeosludge. Also, the treatment of wastewater of pH 7.8 from the same area with high quality HEU-type natural zeolite (88 wt.% clinoptil...
Article
Full-text available
We report on integrated geomorphological, mineralogical, geochemical and biological investigations of the hydrothermal vent field located on the floor of the density-stratified acidic (pH ~ 5) crater of the Kolumbo shallow-submarine arc-volcano, near Santorini. Kolumbo features rare geodynamic setting at convergent boundaries, where arc-volcanism a...
Chapter
This review summarizes the existing data about the geological sources of As in Greece; their variety and the relevant concentrations make Greece a peculiar territory to generalize and better understand the methodology for their assessment. These sources concern As-containing ores in active and abandoned mining areas, geothermal/hydrothermal waters,...
Conference Paper
Full-text available
The Sahara desert is the largest source of dust in the world. Saharan dust is characterized by great com- plexity, composed mainly of mixtures of mineral phases (amorphous or crystalline, with particle sizes of the order of μm or even nm). The presence of amorphous components makes it difficult to detect their struc- ture. For this purpose the spec...
Conference Paper
Full-text available
The important role of metals and metalloids in the aquatic environment can be studied by means of Syn- chrotron Radiation (SR)-based X-ray spectroscopic techniques. In the present work, we have performed analyses of data sets (μ–XRF, μ–XANES and μ–EXAFS), for coastal sediments and marine precipitates, obtained at the ANKA Synchrotron Facility in Ka...
Conference Paper
Full-text available
86 wt.% δεόιηζν ηύπνπ-HEU (θιηλνπηηιόιηζν-επιαλδίηε), 2 wt.% καξκαξπγία θαη 2 wt.% ζκεθηίηε (90 wt.% κηθξνπνξώδε νξπθηά), 5 wt.% αζηξίνπο, 3 wt.% ραιαδία θαη 2 wt.% ρξηζηνβαιίηε. Λέξειρ Κλειδιά: δεν-ιπκαηνιάζπε, βηνκεραληθή δεν-ιάζπε, θπζηθόο δεόιηζνο.
Article
Full-text available
a b s t r a c t A large paleo-river of Miocene age traversing Libya from south to north has been previously demon-strated by seismic, stratigraphic, paleontological, and remote sensing data. The depositional environment of As Sahabi Formation in north central Libya is this large and now extinct Eosahabi River. However, the source of this major Afri...
Article
Full-text available
We studied the geological and technological features of altered pyroclastic rocks from the main Bentomine Kimolian Enterprises S.A. quarry, in the Prassa region on the northeastern part of the Kimolos island, Greece. Particular emphasis was given to a MOR-type (mordenite) zeolite-rich material, tuff, which also contains K-feldspars, opal-CT and cla...
Conference Paper
Full-text available
This is actually a conference extended abstract that concerns a spectroscopic (Mössbauer, XANES and FTIR) and thermal (TGA-DCS) investigation of Greek karst-type bauxites from the Parnassos-Ghiona active mining area. In: Proceedings of the “XXV Panhellenic Conference on Solid State Physics and Materials Science”
Article
Full-text available
Mortar that was used in building as well as in conservation and restoration works of wall paintings have been analysed isotopically (delta(13)C and delta(18)O) in order to evaluate the setting environments and secondary processes, to distinguish the structural components used and to determine the exact causes that incurred the degradation phenomena...