http://hdl.handle.net/10366/154506 2026-04-20T07:43:15Z 2026-04-20T07:43:15Z Pereira Gómez, María Dolores http://hdl.handle.net/10366/161313 2025-07-11T08:49:45Z 2024-01-01T00:00:00Z

[EN] When a historical building, monument, or cultural heritage artifact is affected by a natural or anthropic event, the first reaction is to recover and restore to maintain our heritage for the next generations. If they are made of stone, some are completely destroyed, but it is often still possible to recognize the facts that made them a cultural item. In many cases, the marks of violent actions are visible on the stone, especially if the impacts came from a non-massive destructive weapon, such as rifle bullet marks or cannon marks from centuries ago, with a lower level of destruction than today. These marks are also part of our heritage and, as a reminder of the history of our cities and countries for generations, it is recommended that they be preserved as a testimony to avoid the repetition of unnecessary violence. This is the aim of the stones that tell stories.

2024-01-01T00:00:00Z Navarro, Rafael Monterrubio Pérez, Serafín Pereira Gómez, María Dolores http://hdl.handle.net/10366/155022 2025-04-30T20:39:12Z 2022-01-01T00:00:00Z

[EN]For centuries, granite has been one of the most widely used natural stones for building heritage, especially in the north of the Iberian Peninsula. The sanctuary of La Tuiza in Lubian (Zamora, northwest of Spain), built with Calabor granite, dates from the eighteenth century and was declared an Asset of Cultural Interest in 1995. The heritage importance of this site lies in its location, on the Sanabria route (Silver Route) of the Way of St James (Camino de Santiago), attracting visitors from all over the world. This work presents the complete characterisation of the building stone of both the monument and the original quarry and the qualitative description of the main pathologies that have been detected. The capillary water absorption coefficient is twice the value in the sanctuary compared to the quarry; the open porosity, water absorption at atmospheric pressure and sound speed propagation are slightly higher, and the compressive strength value is lower in the stones of the building. These differences reveal the incipient decay processes. In terms of pathologies, biological colonisation is scattered throughout the building, affecting the north face more intensely, and on the exterior, scaling is observed on the west face. Inside the sanctuary, deterioration is related to humidity due to capillary water infiltration, which causes conspicuous stains, efflorescence and biological colonisation in the western sidewalls. The authors recommend that measures be taken to prevent further deterioration and to protect this small site in order to maintain the cultural heritage linked to the local community.

2022-01-01T00:00:00Z Pereira Gómez, María Dolores http://hdl.handle.net/10366/155020 2024-07-02T08:10:20Z 2023-01-01T00:00:00Z

[EN]Any scientific area can benefit from the contributions of a diverse society. Upon reflection, many notable achievements have been made by women to the advancement of science, but they were not highlighted enough. Such was the case of Hedy Lamarr, who co-authored the development of a radio guidance system (the start of the present Wi-Fi) or Rosalind Franklin, who contributed enormously to the discovery of the structure of DNA. But they were shadowed by their male counterparts. The same happens today. The ratio male/female in most important scientific recognitions, like the Nobel prize, is very illustrative. This situation also applies to the inclusion of female researchers in journal editorial boards, where the main process of manuscripts management takes place. Steps have been done to correct the disparity, but actions need to be reviewed. This paper aims to compare the evolution of gender diversity within the editorial boards of six quality scholarly journals dealing with Earth Sciences to see how gender diversity has been considered in the update of board panels along the years. The conclusions are that there is a long way to go to reach gender diversity, but also that the implementation of constructive changes may trigger a definitive alteration in these trends through good practices.

2023-01-01T00:00:00Z Rivero Crespo, M.A. Pereira Gómez, María Dolores Villa García, V. Gallardo Amores, J.M. Sánchez Escribano, V. http://hdl.handle.net/10366/155006 2025-04-30T20:39:12Z 2019-01-01T00:00:00Z

[EN]Serpentinite powdered samples from four different regions were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), SBET and porosity measurements, UV-Vis and Infrared Spectroscopy of the skeletal region and surface OH groups. SEM micrographs of the samples showed a prismatic morphology when the lizardite was the predominant phase, while if antigorite phase prevailed, the particles had a globular morphology. The few fibrous-shaped particles, only observed by SEM and weakly detected by XRD on MO-9C and MO13 samples, were characteristic of the chrysotile phase. All diffraction XRD patterns showed characteristic peaks of antigorite and lizardite serpentine phases, with crystallite sizes in the range 310–250 Å and with different degrees and types of carbonation processes, one derived from the transformation of the serpentine, generating dolomite, and another by direct precipitation of calcite. The SBET reached values between 38–24 m2∙g−1 for the samples less crystalline, in agreement with the XRD patterns, while those with a higher degree of crystallinity gave values close to 8–9 m2∙g−1. In the UV region all electronic spectra were dominated by the absorption edge due to O2− → Si4+ charge transfer transition, with Si4+ in tetrahedral coordination, corresponding to a band gap energy of ca 4.7 eV. In the visible region, 800–350 nm, the spectra of all samples, except Donai, presented at least two weak and broad absorptions centred in the range 650–800 and 550–360 nm, associated with the presence of Fe3+ ions from the oxidation of structural Fe2+ ions in the serpentinites ((MgxFe2+1−x)3Si2O5(OH)4). The relative intensity of the IR bands corresponding to the stretching modes of the OH’s groups indicated the prevalence of one of the two phases, antigorite or lizardite, in the serpentinites. We proposed that the different relative intensity of these bands could be considered as diagnostic to differentiate the predominance of these phases in serpentinites.

2019-01-01T00:00:00Z Bloise, Andrea Ricchiuti, Claudia Navarro, Rafael Punturo, Rosalda Lanzafame, Gabriele Pereira Gómez, María Dolores http://hdl.handle.net/10366/154925 2026-01-19T11:16:06Z 2021-01-01T00:00:00Z

[EN]The Nevado-Filábride Complex (NFC) area (southern Spain) is well known for the widespread mining and quarrying activities. Serpentinite and metabasite rock types are extracted, processed and traded as building and ornamental stones. Due to possible presence of Naturally Occurring Asbestos (NOA) minerals in these lithotypes, the aim of the investigation of this paper is to discern about the presence of these fibrous minerals and to characterize them in detail. In order to do this, seven serpentinite rock samples were collected in four quarries located in Sierra Nevada and Sierra de los Filabres (South-eastern Spain) and studied by X-ray powder diffractometry (XRPD), Scanning Electron Microscopy combined with Energy-Dispersive Spectrometry (SEM/EDS), Differential scanning calorimetry (DSC), Derivative Thermogravimetry (DTG) and by X-ray Synchrotron microtomography (SR-µCT). The investigation of asbestos minerals is very important not only from a scientific point of view, but also from a legislative one, especially for the administrative agencies that have to take decisions with regards to the implementation of health protection to workers (e. g., quarry excavations, road yards, civil constructions, building stones).

2021-01-01T00:00:00Z Navarro Domínguez, Rafael Catarino, Lidia Pereira Gómez, María Dolores Campos Gil, Francisco Paulo de Sá http://hdl.handle.net/10366/154913 2026-01-19T11:16:56Z 2019-01-01T00:00:00Z

[EN]Colour is an important parameter that must be taken into account if aesthetic homogeneity in both construction and restoration work is to be achieved. In serpentinites, the different degrees of serpentinization or carbonation can influence their final colour. Sunlight, especially ultraviolet (UV) radiation, is a common agent that can decay properties such as hue, lightness, and chroma, and can have a very significant effect on the ageing process of dimension stones. Testing the effects of UV radiation is fundamental for predicting how materials may behave upon exposure. In this work, the surface alteration of materials due to UV radiation by means of arc-xenon lamps was carried out to determine the degree of variation in colour parameters in serpentinites used as dimension stones. It was observed that the effect of UV radiation on the materials studied was low, and that the samples tended to darken and become yellow. Gloss was the parameter that varied the most, which decreased in all the cases analysed. Associations were observed between the loss of gloss and a decrease in some parameters such as open porosity, water absorption at atmospheric pressure and water absorption by capillarity (direct), bulk density and uniaxial compression strength (reverse). The mineralogical composition of the stone was the main factor that influenced the loss of gloss. This research highlights the importance of the detailed study of colour variation in dimension stones due to exposure to UV radiation. The incorrect assessment of the damage that could be caused by this agent can lead to severe aesthetic destruction that may result in expensive legal actions.

2019-01-01T00:00:00Z López, A. Pozo Antonio, S Moreno, Alicia Rivas, Teresa Pereira Gómez, María Dolores Ramil, Alberto http://hdl.handle.net/10366/154870 2026-01-19T11:18:15Z 2022-01-01T00:00:00Z

[EN]In the field of stone conservation, a very common direct intervention seeks to increase the water repellence of objects. By limiting the interaction between the solid and the water, the possibility of alteration due to the action of the water (liquid or solid) as well as that related to the colonisation of surfaces by organisms is reduced. To decrease wettability, chemicals are often applied to create a surface layer; however, laser texturing, currently used in different industrial and technological fields, could be considered as an alternative procedure, thus eliminating exposure to chemicals with varying degrees of toxicity. In this paper, modification of the wetting properties of stone surfaces upon texturing induced by a femtosecond laser structuring process was investigated. Four ornamental stones with different mineralogic and chemical compositions (slate, quartzite, granite and marble) and other surface characteristics were laser processed by applying different texturing patterns (parallel grooves and matrices of craters) and different irradiation parameters. After texturing, variations on the wettability characteristics of the different rock surfaces were evaluated by means of static contact angle measurements and modifications on the topography were studied via confocal microscopy. Furthermore, potential harmful effects on the ornamental stones were evaluated through colour spectrophotometry, petrographic microscopy and SEM-EDX. The results indicate two different behaviours in the ornamental stones analysed that were statistically confirmed: on the one hand, the group formed by slate, quartzite and granite, in which the laser texturing caused a decrease in the contact angle and, on the other hand, marble in which laser texturing was able to increase the contact angle above 90°, giving the stone surface a hydrophobic character. The topographic analyses together with microscopy observations indicate that the grain size, mineral composition, type of fissures and initial surface quality of the stones were key in the different wetting behaviour of the laser textured stones.

2022-01-01T00:00:00Z Navarro, Rafael Pereira Gómez, María Dolores Fernández de Arévalo, Elena Sebastián Pardo, Eduardo Rodríguez-Navarro, Carlos http://hdl.handle.net/10366/154701 2026-01-19T11:20:24Z 2021-01-01T00:00:00Z

[EN]This paper presents a thorough study of the main features and the decay causes and mechanisms of serpentinites both freshly quarried and after centuries exposure at the main façade of the sixteenth century Royal Chancery (Granada, Spain). In particular, the process of in situ formation of calcium and magnesium sulfates has been studied. Several decay factors are identified, all of them acting synergistically in the deterioration of slabs made of serpentinite. Among them, chemical weathering of sulfides such as pyrite present in the original serpentinite induces the formation of sulfate salts such as gypsum or epsomite, salts which are considered the main cause of decay. In addition, unsuitable restoration treatments involving the use of Portland cement to fill up cracks and surface lacunae, the polluted environment of the surrounding area, and the location of the slabs close to the ground, favoring capillary rise of water, all contributed to their deterioration. This work helps to gain knowledge on the deterioration process of ornaments made of serpentinite, allowing us to propose the most appropriate measures to guarantee their conservation.

2021-01-01T00:00:00Z Pereira Gómez, María Dolores http://hdl.handle.net/10366/154700 2024-07-02T08:13:13Z 2023-01-01T00:00:00Z

[EN]The use of stone to build shelters was an important step in terms of ensuring buildings’ durability and security in pre-historic times. It was also an acknowledgment of power and grandeur when societies demonstrated their respect for their leaders and gods by building stone monuments. For this reason, cathedrals, churches, and other magnificent religious monuments were built around the globe; however, the importance of the stone used in their construction itself is not sufficiently appreciated as the key factor ensuring the endurance of these historic buildings. While Western countries have long used iconic buildings to promote their heritage and advance in other socio-economic aspects, including tourism, other regions are yet to take full advantage of this outlook, even though their monumental structures may be equally impressive. Those important monuments are built of stone, which were referred to as Heritage Stones by some research groups, and their recognition would showcase the cultural and geological diversity of the world. However, there are many stones of heritage importance from geographic areas that are under-represented in the scientific literature and the work of research groups. This paper presents a review of the degree of geographical diversity in the recognition of stones and their heritage value.

2023-01-01T00:00:00Z Pereira Gómez, María Dolores López, Ana J. Ramil, Alberto Bloise, Andrea http://hdl.handle.net/10366/154698 2026-01-19T11:21:42Z 2022-01-01T00:00:00Z

[EN]Health risks are often overlooked when the consequences are not evident in the short term. In restoration work, some activities can generate particles that may affect the health of workers through inhalation (e.g., cleaning of buildings or heritage artifacts composed of stone). Workers at quarries are also exposed to such materials and, therefore, the results of our work can help to increase the risk perception in workers from the stone sector, but also in construction workers in an environment associated with dust. To demonstrate the importance of protection to prevent health hazards, we laser-ablated some samples of serpentinite that contain serpentine minerals as major phase minerals. The powder obtained in filters coupled to the ablation laser was analysed, using tools such as an optical microscope, X-ray powder diffraction, a transmission electron microscope and thermal analysis. The results were very didactic, and the intention is to use them, by way of graphics and diagrams, to build information security sheets that will alert workers to the need of using masks when working, or to use tools with coupled filters such as the one used for our study. The main goal is to demonstrate that the interdisciplinary combination of scientific approaches can be used for the sake of human health.

2022-01-01T00:00:00Z Bloise, Andrea Ricchiuti, Claudia Punturo, Rosalda Pereira Gómez, María Dolores http://hdl.handle.net/10366/154692 2026-01-19T11:22:24Z 2020-01-01T00:00:00Z

[EN]Potentially toxic elements (PTEs) hosted in asbestos elongate mineral particles is one of the factors that determines their toxic/pathogenic effects. This study quantifies and compares these elements in terms of major, minor and trace element concentrations (Si, Mg, Ca, Al, Fe, Mn, Cr, Co, Ni, Cu, Zn, Be, V, As, Rb, Sb, Ba, Pb, Sr) in various types of asbestos using micro X-ray fluorescence (μ-XRF) and inductively coupled plasma mass spectrometry (ICP-MS), in order to understand how they contribute to asbestos-related diseases. Chrysotile, tremolite asbestos and actinolite asbestos extracted from the Gimigliano-Mount Reventino Unit (Calabria Region, Southern Italy) were used for this study. In the minerals analysed, high concentrations of Cr (171 ppm) and Be (2.9 ppm) were found in tremolite asbestos and chrysotile respectively. When calculating the pseudo-total concentrations of trace elements in the samples, the largest amounts were detected in tremolite asbestos, followed by actinolite asbestos and chrysotile. However, since other metals such as Mn and Fe (minor elements) are known to induce toxicity, and considering their input to the overall balance, actinolite contained the largest amount of PTEs and in this case chrysotile proved to be more toxic than tremolite asbestos. Furthermore, the potential leaching of PTEs, released by chrysotile, tremolite and actinolite asbestos-containing rocks, into the soil and water supply is also discussed. Since asbestos elongate mineral particles can be widespread in the environment (i.e. air, rocks, soil, water), it is essential to quantify the toxic elements present in asbestos elongate mineral particles in order to prevent asbestos-related diseases. The knowledge obtained from this study will provide us with a better understanding of asbestos-related lung cancer.

2020-01-01T00:00:00Z Monterrubio Pérez, Serafín Navarro, Rafael Pereira Gómez, María Dolores http://hdl.handle.net/10366/154607 2026-01-19T11:23:03Z 2020-01-01T00:00:00Z

[EN]Workers carrying out actions involving potential hazards, like mining and quarrying, can be subject to health issues derived from those activities. The case of asbestosis has generated an alarm in the society. Natural stones are very different from each other and generalisation can cause, first an unwanted alarm, and secondly a big economic crisis in the sector of the natural stone, as it has happened before with other health issues related to exploitation and use of natural stone in architecture. This paper highlights the need for an appropriate mineralogical characterization of rocks of economic interest, such as serpentinites, to protect mining workers of health issues derived from fibrous minerals content. We have studied the possible presence of fibrous minerals in samples of serpentinites from an abandoned quarry in Galicia (North Western Spain) to consider the viability of its re-opening based on the Spanish health and safety regulations applicable to jobs at risk of exposure to asbestos. From our study, it can be concluded that there is a scarce amount of fibrous phases, pending on further studies to differentiate such fibrous minerals, and therefore the reopening of the serpentinite quarry should not be a health problem for the workers.

2020-01-01T00:00:00Z Pereira Gómez, María Dolores http://hdl.handle.net/10366/154603 2026-01-19T11:23:49Z 2023-12-01T00:00:00Z

[EN]Any scientific area can benefit from the contributions of a diverse society. Upon reflection, many notable achievements have been made by women to the advancement of science, but they were not highlighted enough. Such was the case of Hedy Lamarr, who co-authored the development of a radio guidance system (the start of the present Wi-Fi) or Rosalind Franklin, who contributed enormously to the discovery of the structure of DNA. But they were shadowed by their male counterparts. The same happens today. The ratio male/female in most important scientific recognitions, like the Nobel prize, is very illustrative. This situation also applies to the inclusion of female research- ers in journal editorial boards, where the main process of manuscripts management takes place. Steps have been done to correct the disparity, but actions need to be reviewed. This paper aims to compare the evolution of gender diversity within the editorial boards of six quality scholarly journals dealing with Earth Sciences to see how gender diversity has been considered in the update of board panels along the years. The conclusions are that there is a long way to go to reach gender diversity, but also that the implementation of constructive changes may trigger a definitive alteration in these trends through good practices.

2023-12-01T00:00:00Z Pereira, Dolores Tejado, Juan José Mota, María Isabel http://hdl.handle.net/10366/154555 2025-04-30T20:39:14Z 2021-03-01T00:00:00Z

Granite quarrying is one of the main industries operating in Spain, and was severely affected by the economic crisis that began in 2008. Although the industry is slowly recovering from this event, new construction activity has not fully recovered. For a company to be competitive in the stone market, it must consider the overall characteristics of the materials it provides and their importance with regard to architectural heritage, with the aim of using original types of stone in restorations. In the area of Trujillo (Extremadura, Spain) a variety of striking bluish and secondary yellow granites outcropping within the Plasenzuela pluton have been analysed. These two varieties are quarried under different names and petrographically characterized by leucocratic minerals with a bluish phosphate dispersed throughout the rock. Their physical and mechanical properties make these granites a perfect option for most applications as ornamental rocks. The bluest variety, Azul Platino, has been used in local, national and international projects and fulfils the necessary requirements that would allow it to be considered a Global Heritage Stone Resource (GHSR).

2021-03-01T00:00:00Z