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This article reports on a compositional investigation of stone patinas: thin colored layers applied for protective and/or aesthetic purposes on architectural or sculptural substrates of cultural heritage. The analysis and classification of patinas provide important information of historic and artistic interest, as their composition reflects local practices, the availabilities of different materials, and the development of technological knowledge during specific historical periods. Model patinas fabricated according to traditional procedures and applied onto limestone, and a historic patina sample from the main façade of the San Blas Monastery in Lerma (a village in the province of Burgos, Spain), were analyzed by laser-induced fluorescence and Fourier transform Raman spectroscopy. The results obtained demonstrate the ability of these two analytical techniques to identify the key components of each formulation and those of the reaction products which result from the chemical and mineralogical transformations that occur during aging, as well as to provide information that can aid the classification of different types of patinas. ; This work has been funded by the Madrid Regional Government project Geomateriales (S2009/Mat-1629) and by the Ministerio de Ciencia e Innovación under projects CTQ2010-15680 and CONSOLIDER CSD2007-00058. ; Peer Reviewed

7 pags., 6 figs. ; The evolution of the magnetic anisotropy directions has been studied in a magnetite (FeO) thin film grown by infrared pulsed-laser deposition on SrTiO(100):Nb substrate. The magnetic easy axes at room temperature are found along the in-plane 〈100〉 film directions, which means a rotation of the easy axis by 45° with respect to the directions typically reported for bulk magnetite and films grown on single-crystal substrates. Moreover, when undergoing the Verwey transition temperature, T, the easy axis orientation evolves to the 〈110〉 film directions. This anomalous behavior has been demonstrated by measuring first the angular dependence of coercivity and remanence well above and below T by high-resolution vectorial magneto-optical Kerr effect (v-MOKE). Ferromagnetic resonance (FMR) measurements have additionally proven a well-defined fourfold magnetic anisotropy induced during growth with confirmed easy axis directions along 〈100〉 for T > T and 〈110〉 for T < T. These results provide a clear proof of the possibility of tuning magnetic anisotropy in FeO thin films by proper control on the growth parameters and substrate choice. ; This research was supported by the Regional Government of Madrid through NANOMAGCOST project (P2018/NMT-4321) and by the Spanish Ministry of Economy and Competitiveness (MINECO) through Project CTQ2016-75880-P. M. O. thanks CSIC for contract and E. R. thanks MINECO for the tenure of a Ramón y Cajal contract (No. RYC-2011-08069). The work in Lausanne was supported by the Sinergia grant "Mott physics beyond the Heisenberg model" of the Swiss NSF. The work in BUTE (Hungary) was supported by NKFIH Grant No. K119442 and 2017-1.2.1-NKP-2017-00001, and by the BME-Nanotechnology FIKP grant of EMMI (BME FIKP-NAT). IMDEA Nanoscience is supported by the 'Severo Ochoa' Programme for Centres of Excellence in R&D, MINECO [grant number SEV-2016-0686]

Esta comunicación participó en el: 5th International Conference YOuth in COnservation of CUltural Heritage YOCOCU 2016 21st-23rd September 2016 Madrid ; Very recently, in monumental cities, certain conservational practices tend to use ancient/traditional roof tiles in the restoration of Heritage buildings. Numerous studies have been undertaken to remove lichens on stones. However, little has been done to date to study lichens removal from ceramic materials, despite the fact that they are commonly colonized by different lichen communities. The main goal of this contribution is making a diagnosis of alterations that lichens may cause in ceramic materials, as well as to determine the possibilities of removal by treatments based on laser irradiation and use of biocides. ; Geomateriales 2 (Ref. S2013/MIT-2914, Regional Government of Madrid and EU structural funds) and IPERION-CH (Integrated Platform for the European Research Infrastructure on Cultural Heritage (Ref. H2020-INFRAIA-2014-2015 nº 654028). ; Peer Reviewed