{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T17:48:05Z","timestamp":1770745685313,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2023,8,3]],"date-time":"2023-08-03T00:00:00Z","timestamp":1691020800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"DEMORA project","award":["PID2020-113391GB-I00"],"award-info":[{"award-number":["PID2020-113391GB-I00"]}]},{"name":"Spanish Agency for Research (through the Spanish Ministry of Science and Innovation, MICINN, and the European Regional Development Fund, FEDER)","award":["PID2020-113391GB-I00"],"award-info":[{"award-number":["PID2020-113391GB-I00"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In this work, some micro-samples belonging to the open-air rock art site of Cueva de la Vieja (Alpera, Albacete, Spain) were analysed. These samples were collected after and before a desalination treatment was carried out, with the aim of removing a whitish layer of concretion that affected the painted panel. The diagnostic study was performed to study the conservation state of the panel, and to then confirm the effectiveness of the treatment. Micro energy dispersive X-ray fluorescence spectrometry, Raman spectroscopy, and X-ray diffraction were employed for the characterization of the degradation product as well as that of the mineral substrate and pigments. The micro-samples analysis demonstrated that the painted layer was settled on a dolomitic limestone with silicon aggregates and aluminosilicates as well as iron oxides. The whitish crust was composed by sulfate compounds such as gypsum (CaSO4\u00b72H2O) with a minor amount of epsomite (MgSO4\u00b77H2O). An extensive phenomenon of biological activity has been demonstrated since then in almost all of the samples that have been analysed, and the presence of calcium oxalates monohydrate (CaC2O4\u00b7H2O) and dehydrate (CaC2O4\u00b72H2O) were found. The presence of both calcium oxalates probably favoured the conservation of the pictographs. In addition, some carotenoids pigments, scytonemin (C36H20N2O4), and astaxanthin (C40H52O4) were characterized both by Raman spectroscopy and by X-ray diffraction. Hematite was found as a pigment voluntarily used for the painting of the panels used in a mixture with hydroxyapatite and amorphous carbon. The results of the analyses of the samples taken after the cleaning treatment confirmed a substantial decrease in sulphate formation on the panel surface.<\/jats:p>","DOI":"10.3390\/molecules28155854","type":"journal-article","created":{"date-parts":[[2023,8,3]],"date-time":"2023-08-03T11:23:03Z","timestamp":1691061783000},"page":"5854","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Study of Micro-Samples from the Open-Air Rock Art Site of Cueva de la Vieja (Alpera, Albacete, Spain) for Assessing the Performance of a Desalination Treatment"],"prefix":"10.3390","volume":"28","author":[{"given":"Ilaria","family":"Costantini","sequence":"first","affiliation":[{"name":"Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV\/EHU, P.O. Box 644, 48080 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3728-8370","authenticated-orcid":false,"given":"Julene","family":"Aramendia","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV\/EHU, P.O. Box 644, 48080 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4649-2381","authenticated-orcid":false,"given":"Nagore","family":"Prieto-Taboada","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV\/EHU, P.O. Box 644, 48080 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7854-855X","authenticated-orcid":false,"given":"Gorka","family":"Arana","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV\/EHU, P.O. Box 644, 48080 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1685-6335","authenticated-orcid":false,"given":"Juan Manuel","family":"Madariaga","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV\/EHU, P.O. Box 644, 48080 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7309-0102","authenticated-orcid":false,"given":"Juan Francisco","family":"Ruiz","sequence":"additional","affiliation":[{"name":"Department of History, Area of Prehistory, Faculty of Education Sciences and Humanities, University of Castilla-La Mancha (UCLM), Avda. de los Alfares 42, 16002 Cuenca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"eabd4648","DOI":"10.1126\/sciadv.abd4648","article-title":"Oldest Cave Art Found in Sulawesi","volume":"7","author":"Brumm","year":"2021","journal-title":"Sci. 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