168601 20260212204407.0 doi 10.3390/min16020178 sideral 148017 ART-2026-148017 eng Yuste, Alfonso Universidad de Zaragoza (orcid)0000-0002-2169-4561 Exploring Lower Cretaceous Karst Bauxite from South-Central Pyrenean Unit (NE Spain): Genesis and Ceramic Potential 2026 Access copy available to the general public Unrestricted This study investigates a karst bauxite deposit from NE Spain with a dual objective incorporating the novel aspect of directly linking genetic processes to industrial ceramic performance. First, the bauxite is mineralogically and texturally characterized using X-ray diffraction and field emission scanning electron microscopy. Second, the mineralogical and textural transformations of the bauxite during firing at 1000, 1200 and 1300 °C are analyzed, together with their effects on the physical properties of the fired products. The Lower Cretaceous bauxite is autochthonous, shows a pisolithic structure, and formed in situ under tropical monsoon conditions through intense chemical weathering involving dissolution–crystallization processes. For ceramic testing, the bauxite was mixed with illitic–kaolinitic clays in a 90/10 proportion. During firing, kaolinite and illite destabilize and transform into mullite, initially by solid-state reactions at 1000 °C and subsequently by crystallization from a vitreous phase at higher temperatures, producing larger crystals and composition closer to the empirical mullite formula. The formation of vitreous phase and mullite leads to reduced porosity and increased density and linear shrinkage, particularly between 1000 and 1200 °C. Specimens fired at 1300 °C show higher mechanical strength, related to higher mullite content and a larger size of its crystals. The results demonstrate the potential interest of these bauxites for ceramic manufacturing. info:eu-repo/grantAgreement/ES/MCIU/PID2021-123127OB-I00 nfo:eu-repo/grantAgreement/ES/MICINN/JDC2022-048348-I info:eu-repo/semantics/openAccess by https://creativecommons.org/licenses/by/4.0/deed.es info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Bauluz, Blanca Universidad de Zaragoza (orcid)0000-0002-4970-6333 Laita, Elisa 2000 120 Universidad de Zaragoza Dpto. Ciencias de la Tierra Área Cristalografía Mineralog. 16, 2 (2026), 178 [23 pp.] Minerals (Basel) Minerals 2075-163X 14166066 http://zaguan.unizar.es/record/168601/files/texto_completo.pdf Versión publicada 2429964 http://zaguan.unizar.es/record/168601/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:168601 articulos driver 2026-02-12-20:41:35 ARTICLE