Heritage Stone 4. The Piedra Berroqueña Region: Candidacy for Global Heritage Stone Province Status

The Piedra Berroqueña region in the Guadarrama Mountains, part of Spain’s Central Range, supplies most of the construction granite used in Madrid and surrounding provinces. The region’s quarrying towns preserve their granite extraction and hewing traditions. Historic quarries form part of the landscape, as do current extraction sites with huge reserves that guarantee a speedy supply of variously finished dimension stone. Piedra Berroqueña granite has been in use as a construction material since long before Roman times. Many important monuments, including San Lorenzo Royal Monastery at El Escorial (1563−1584), Madrid’s Royal Palace (1738−1764), the Alcalá Gate (1770−1778), the Prado Museum (1785−1808) and Puerta del Sol (one of Madrid’s main squares), owe their good state of preservation to the stone’s petrophysical characteristics and durability. The granite is also found in most of the city’s housing and streets, as well as in modern buildings the world over, such as the airport terminals at Athens and Cork, and the British consulate at Hong Kong.   Four major types of monzogranite occur including: biotitic monzogranites containing some cordierite, biotitic monzogranites containing some amphibole, biotitic monzogranites having no cordierite or amphibole, and leucogranites. The petrological, petrophysical and chemical properties of Piedra Berroqueña, which afford it great durability, vary little from one variety to another and depend on the degree of alteration. Physical and chemical characteristics were determined for five granites representative of historic or active quarries in the Piedra Berroqueña region: Alpedrete (monzogranite containing cordierite); Cadalso de los Vidrios (leucogranite); La Cabrera (monzogranite containing amphibole); Colmenar Viejo (monzogranites containing cordierite) and Zarzalejo (monzogranites having no cordierite or amphibole).    The Piedra Berroqueña region meets the requirements of a Global Heritage Stone Province, and this paper supports the Piedra Berroqueña region's application for recognition as such. This distinction would enhance public awareness of an area committed to quarrying and working the local stone.RÉSUMÉLa région de Piedra Berroqueña dans les monts de Guadarrama, qui fait partie de la chaine centrale d'Espagne, est la principale source du granite de construction utilisé à Madrid et dans les provinces environnantes. Les agglomérations de la région qui exploitent une carrière conservent leur tradition d’extraction et de taille du granite. Les anciennes carrières font maintenant partie du paysage, comme les sites d'extraction actuels avec d'énormes réserves ce qui garantit un approvisionnement rapide en pierre de taille de fini varié. Le granite de Piedra Berroqueña a été utilisé comme matériau de construction bien avant l'époque romaine. De nombreux monuments importants, y compris le monastère royal de San Lorenzo à l'Escurial (1563–1584), le palais royal de Madrid (1738–1764), la porte d'Alcalá (1770–1778), le musée du Prado (1785–1808) et la Puerta del Sol (une des principales places de Madrid), doivent leur bon état de conservation aux caractéristiques pétrophysiques et à la durabilité de la pierre. Ce granite se retrouve également dans la plupart des habitations et des rues de la ville, ainsi que dans des bâtiments modernes du monde entier, tels que les terminaux de l'aéroport d'Athènes et de Cork, et le consulat britannique à Hong Kong.   Il est constitué de quatre grandes classes de monzogranite : des monzogranites à biotite contenant un peu de cordiérite, des monzogranites à biotite contenant un peu d’amphibole, des monzogranites à biotite ne contenant ni cordiérite ni amphibole, et les leucogranites. Les propriétés pétrographiques, pétrophysiques et chimiques des granites de Piedra Berroqueña qui leur assurent une grande durabilité, varient peu d'une variété à l'autre et dépendent du degré d'altération. Les caractéristiques physiques et chimiques ont été déterminées sur cinq granites représentatifs des carrières historiques et actives de la région de Piedra Berroqueña : Alpedrete (monzogranite à cordiérite); Cadalso de los Vidrios (leucogranite); La Cabrera (monzogranite à amphibole); Colmenar Viejo (monzogranite à cordiérite); et Zarzalejo (monzogranite sans cordiérite ni amphibole).   La région Piedra Berroqueña répond aux critères d'une Province pétrologique du patrimoine mondial, et le présent article documente la candidature de la région de Piedra Berroqueña à cet effet. Cette distinction permettrait d'améliorer la sensibilisation du public concernant une région spécialisée dans l’extraction et à la taille de la pierre locale.                                                      Traduit par le Traducteu

Damage in the Cadalso de los Vidrios Granite under water freeze/thaw conditions

The repeated action of simulated freeze-thaw cycles on Cadalso de los Vidrios Granite, promotes differential micro-cracking and loss of cr ystals at the surface and therefore decay. It is possible to establish a relationship between the evolution of the ultrasound waves velocity (Vp) with the number of freeze-thaw cycles and the generation of microcracks. Intergranular cracks are formed during the first cycles and these propagate towards the inner part of each individual crystals as the freeze-thaw cycles advance. Therefore, after 280 freeze-thaw cycles different patterns of microcracking can be observed depending on the mineralogy. Quartz is the mineral displaying more intense cracking while biotite shows less cracking, in part due to its more ductile behaviour. Micro-cracks appear preferentially at the surface of the samples with a maximum length and depth of 1 cm. Thus, these samples showed limited decay highlighting the good performance of Cadalso de los Vidrios granite against freezetha

El granito como piedra de construcción en Madrid: durabilidad y puesta en valor

La tesis titulada “El granito como piedra de construcción en Madrid: durabilidad y puesta en valor” está estructurada en 6 artículos científicos publicados, 1 aceptado y otro en revisión, en diferentes revistas internacionales indexadas y un capítulo de un libro divulgativo. El uso de la piedra de construcción ha estado determinado por la proximidad de los recursos geológicos. Los materiales pétreos que históricamente se han utilizado en la Comunidad de Madrid provienen del Sistema Central Español y de la cuenca terciaria de Madrid. El sílex ha sido utilizado desde el siglo IX hasta el XI, cuando fue paulatinamente sustituido por la dolomía de Redueña y el granito, llamado tradicionalmente “piedra berroqueña” (Fort et al., 2013a, b). Los avances tecnológicos del siglo XVIII favorecieron la cantería subterránea de la caliza de Colmenar de Oreja. Sin embargo, la piedra berroqueña extraída a cielo abierto ha proporcionado la mayoría de la piedra de construcción utilizada en Madrid. La piedra berroqueña ha representado durante siglos la principal actividad económica en muchos pueblos de la Sierra de Guadarrama (Freire-Lista y Fort, 2015a, b). Estas sierras forman parte del Sistema Central Español. Se extienden en dirección suroeste-noreste a través de las provincias de Madrid, Segovia y Ávila. Ocupa un área aproximada de 100 km de largo por 40 km de ancho en donde existen diversas variedades de granito. Esta piedra ha dado origen a un elevado número de construcciones que suponen un importante pilar en el turismo histórico, cultural y rural del que disfruta actualmente la Comunidad de Madrid..

Comparación de propiedades petrográficas y petrofísicas de tres fragmentos escultóricos para determinar su pertenencia al sepulcro de Nuno Freire de Andrade II (siglo XIV)

Three fragments of stone representing a head, a body and a sarcophagus lid, and attributed to the grave of Nuno Freire de Andrade II, Grand Master of the Order of Christ (fourteenth century), were analysed to determine their petrographic, ultrasonic P-wave pulse velocity, and colour properties. The results indicate that the stones correspond to three lithological types (ortogneis, granodiorite and leucogranite) with different ultrasonic P-wave pulse velocity, colour and colour variation between dry and wet. From these data it is inferred that none of the three fragments have been part of the same sarcophagus lid, since the granite lids of medieval Galician sarcophagus were carved in a single block of stone.Tres fragmentos de piedra que representan una cabeza, un cuerpo y una tapa de sarcófago atribuidos a la lauda de Nuno Freire de Andrade II, Gran Maestre de la Orden de Cristo del siglo XIV, fueron analizados para determinar sus propiedades petrográficas, velocidad de propagación de ondas de ultrasonido y color. Los resultados indican que las piedras corresponden a tres tipos litológicos con distinta petrografía, velocidad de propagación de ondas P, color y variación de color entre secas y húmedas. El fragmento de la cabeza corresponde a un ortogneis, el del cuerpo a una granodiorita y el de la tapa de sarcófago a un leucogranito. A partir de estos datos se infiere que ninguno de los tres fragmentos ha formado parte de la misma lauda, ya que las tapas de sarcófagos medievales gallegas talladas en granito estaban hechas en un único bloque de piedra

Multi-Analysis Characterisation of a Vernacular House in Doha (Qatar): Petrography and Petrophysics of its Construction Materials

This study characterises the original construction materials (building stones and mortars) of a collapsed two-storey colonnaded structure in the Ismail Mandani house, located in the old city centre of Doha (Qatar). Results were drawn based on interpretation and integration of historical, in situ observations and analytical data. The mortars and stones were characterised following a multidisciplinary approach, combining macroscopic observation with petrographic microscopy, mineralogical analysis (X-ray diffraction) and elemental analysis (handheld X-ray fluorescence) of samples. Moreover, hydric properties, ultrasonic pulse velocity and colour of representative samples of the house were studied. The results revealed the use of two types of stones and three different types of gypsum mortars. The original construction materials came from nearby coastal stones. Gypsum of the most used mortar had a calcination temperature between 120 and 160 °C and its colour was produced by lumps with higher Fe content. The materials’ effective porosity and water absorption were high, and their ultrasonic pulse velocity was low. These petrophysical results indicated they had low quality for construction purposes. The composition and colour of the original construction materials were quantified, which will allow the reproduction of their aesthetic characteristics and improvement of their quality in future reconstruction works

Estimating compressive and flexural strength of travertines with respect to laminae-orientation by geomechanical properties

Travertine is an anisotropic rock considered as one of the most popular stone materials in the building industry. Due to its bedding and lamination planes, the determination of rock strength properties regarding anisotropic orientation is a critical issue. In this research, different techniques were applied to estimate the compressive and flexural strengths of four types of travertines, selected from Hamedan and Markazi Provinces located in the west and central parts of Iran. For this purpose, after sample preparation and assessment of mineral composition, fabric (texture and structure) and pore characteristics (pore shape and pore sizes), the selected samples were characterized using physical and mechanical tests. These properties were evaluated with respect to two major anisotropic orientations (perpendicular and parallel to the bedding/lamination axis). Statistical analyses, including simple and multiple linear regressions, were utilized to correlate physical and mechanical parameters with compressive and flexural strength, and to establish some new equations. Based on the test results, it can be concluded that the percentage/type of matrix and porosity have a more important effect on the physical and mechanical properties than the rock structure. Data analysis in simple regression shows that bulk specific gravity (saturated surface dry) and Brazilian tensile strength are the most and least influential factors on compressive strength at perpendicular and parallel directions, respectively. In addition, effective porosity and Brazilian tensile strength are the most and least influential factors on flexural strength at both directions, respectively. Based on best subset multiple regression method, one or two equations were extracted for calculating compressive and flexural strength in the perpendicular and parallel directions. Also, pore shape factor and pore radius were used as independent parameters in multiple regression to establish some new equations for predicting compressive and flexural strength considering cutting directions. These parameters have more influence on flexural strength than compressive strength, because the parameters show significant correlation with flexural strength. Consequently, the results of statistical analyses show that the proposed equations are not necessarily composed of parameters with the higher/stronger determination coefficient in simple regression. Therefore, prediction studies not only offer some rational approaches, they also give a better insight into the main factors determining rock strength

Petrographic and petrophysical characterisation and structural function of the heritage stones in Fuwairit Archaeological Site (NE Qatar): implications for heritage conservation

Several types of limestones have been traditionally used for building mosques, houses and sheds in the Fuwairit archaeological site (NE Qatar). These limestones were characterised, and profiles of semi-collapsed walls examined to estimate the percentage that each building stone occupied and its structural function. Holocene beachrocks were the most used building stones. They were installed mainly as header masonry stones in the walls following coursed random rubble masonry. Pleistocene oolites were used mainly as stretcher masonry stones and Umm Bab Member of Dammam Formation (middle Eocene) as wedges and filling stones of the inner cores between the masonry wall faces. These last building stones were collected in the rocky desert, whose surface is covered by stone fragments resulting from thermal dilatation. Therefore, thermal expansion measurements were performed to investigate the breakage of the Umm Bab Member. Umm Bab Member has the lowest effective porosity and water absorption, and the highest bulk density and ultrasonic pulse velocity. This stone presents the best quality. Oolites have an intermediate quality and beachrocks have the worst quality as building stone. Historic quarries of oolites were found with abandoned stone blocks in Jebel Fuwairit fossil dunes

Geomonumental Route by Manzanares el Real (Madrid)

Manzanares el Real tiene un amplio patrimonio geológico. Está ubicado en el Parque Natural de la Sierra de Guadarrama (Madrid) y sus características geo­lógicas y monumentales posibilitan acciones de divulgación científica. Las Rutas Geomonumentales tienen como objetivo principal mostrar a la sociedad el patri­monio cultural, dándole un uso turístico y didáctico. Estas rutas combinan valores arquitectónicos e históricos con la geología y la conservación del patrimonio. El granito es la piedra de construcción más importante a lo largo de la historia de la región de Madrid. Sus canteras históricas, formas de extracción y usos cons­tituyen un patrimonio que se debe salvaguardar. Este artículo propone un recorrido de siete paradas por canteras históricas y monumentos que constituyen un museo geológico al aire libre. Esta ruta surge a partir de los trabajos de inves­tigación realizados en la Fuente de las Ermitas de Manzanares el RealManzanares el Real has an extensive geological heritage. It is located in the Natural Park of the Sierra de Guadarrama (Madrid), whose geological and monumental features make possible scientific dissemination actions. The main objective of Geomonumental Routes is to show the society the cul­tural heritage, giving it a touristic and didactic use. These routes combine architectural and historical values with geology and he ritage conservation. Granite is the most important building stone in the history of the Madrid re­gion . Its historic quarries, forms of extraction and uses constitute a heritage that must be safeguarde d. This article proposes a tour of seven stops by his­torical quarries and monuments that constitute an open- air geological mu­seum in Manzanares el Real. This route arises from the research work carried out in the Fuente de las Ermitas of this localit

Evaluation of post-thermal shock effects in Carrara marble and Santa Caterina di Pittinuri limestone

This article describes the effect of thermal shock on the petrographic and petrophysical properties of two Italian carbonate building stones: Carrara marble from the Apuan Alps in Tuscany and ‘Santa Caterina di Pittinuri’ limestone, from Sardinia. The samples were exposed to two thermal cycles to study surface and inner stone decay. The changes induced by thermal shock were assessed in terms of microstructural alterations measured with ultrasonic pulse velocity, Hg intrusion porosimetry, polarised light and fluorescent optical microscopy and micro-computed tomography. Variations in surface microhardness were also measured. The marble developed a dense network of pseudo-parallel intercrystalline, intracrystalline and transcrystalline microcracks, whereas the limestone underwent no significant microcracking. Those findings attested to lower resistance to thermal shock in marble calcite crystals than in limestone sparite cement and micrite. Thermal shock, an accelerated weathering technique, simulates possible stone exposure to high temperatures over long periods of time. Here the method was used to evaluate and compare microcrack distribution and orientation in the two heritage stones studied

Ghaleh-khargushi rhyodacite and Gorid andesite from Iran: characterization, uses, and durability

Durability of building stones is an important issue in sustainable development. Crystallization of soluble salts is recognized as one of the most destructive weathering agents of building stones. For this reason, durability of Ghaleh-khargushi rhyodacite and Gorid andesite from Iran was investigated against sodium sulfate crystallization aging test. Petrographic and physico-mechanical properties and pore size distribution of these stones were examined before and after the aging test. The characteristics of the microcracks were quantified with fluorescence-impregnated thin sections. Durability and physico-mechanical characteristics of Ghaleh-khargushi rhyodacite are mainly influenced by preferentially oriented preexisting microcracks. Stress induced by salt crystallization led to the widening of preexisting microcracks in Ghaleh-khargushi rhyodacite, as confirmed by the pore size distributions before and after the aging test. The preexisting microcracks of Gorid andesite were attributed to the mechanical stress induced by contraction of lava during cooling. The number of transcrystalline microcracks was significantly increased after the aging test. The degree of plagioclase microcracking was proportional to its size. Durability of the studied stones depends on initial physico-mechanical properties, pore size distribution, and orientation of microcracks. Initial effective porosity is found to be a good indicator of the stones’ durability. Salt crystallization resulted in an increase in the effective porosity with a parallel decrease in the wave velocities. Surface microroughness parameters increased with the development of salt crystallization-induced microcracking. Gorid andesite showed higher quality and durability than Ghaleh-khargushi rhyodacite