[en] The Martinamor quarries, consisting of tourmaline leucogranites, have been documented as a source material for many post-medieval historical buildings of Salamanca and Alba de Tormes. The granite itself outcrops as a thin, shallowly northward-dipping sheet-like intrusion, belonging to a phase-3 Variscan antiform. Apart from its short distance from the city of Salamanca, several significant criteria can be considered to account for the successful use of the Martinamor granite: 1) petrographic, such as its quartz- and alkali feldsparrich composition, scarce biotite and scarce Ca-rich minerals, as well as a microscopic-scale inequigranular interlobate texture with a strong quartzfeldspatic interlocking; 2) geochemical, showing high-silica contents; and 3) physical-mechanical properties, having low porosity values (0,75-0,86%) and low capillary absorption and imbibition coefficients. All these features result in a hard and consistent stone that has been used for more than 400 years (1515-1932) in Salamanca and Alba de Tormes. Three periods have been distinguished: 1) an initial period, in which the architect Juan de ?lava may have introduced the stone for transitional Gothic-Renaissance buildings; 2) a main period, linked to the Lisbon earthquake (1755 A.C.), making reinforcement of the New Cathedral necessary, together with the construction of magnificent new buildings of Neoclassic style; and 3) a period of functional use, in which Martinamor stone has been systematically used for the foundations of new buildings as a result of urban alignments during the nineteenth century. Also, in the late nineteenth and early twentieth century Martinamor granite was used in many historic buildings as ashlar material where a replacement has been required. In order to recognize the reposition blocks several criteria have been proposed: a) remains of abandoned wedges at the top of the blocks; b) the diversity of the nature of the blocks in the same course; c) mismatching of courses; and d) old photographic documentation. Its use in steps and pavements from the sixteenth century onwards was also due to its hardness and consistency. Finally, an aesthetically based use seems to have played a role, taking advantage not only of the enclavefree homogeneous fabric and hand-scale overall equigranular texture, but also the non-conspicuous light colour of the stone, the former quality being exploited for Renaissance and Neoclassic style buildings, whereas the latter one proved to be a suitable quality for block reposition in Plateresque-style monuments.

[es] El leucogranito turmalin?fero o ?piedra de Martinamor? se ha utilizado en muchos monumentos de Salamanca y Alba de Tormes con posterioridad a la ?poca medieval. De acuerdo con la documentaci?n hist?rica, las canteras se localizan en las cercan?as de Martinamor, localidad distante unos 20 km al S de Salamanca. El granito aflorante define un cuerpo laminar de escasa potencia y d?bilmente buzante al N, como consecuencia del efecto deformativo de la antiforma de Martinamor de fase 3 herc?nica. Aparte de su situaci?n cercana a Salamanca, la exitosa utilizaci?n del granito de Martinamor es justificable por sus cualidades de dureza y consistencia, que, a su vez, se relacionan con los siguientes aspectos: 1) petrogr?ficos, trat?ndose de leucogranitos de feldespato alcalino, con alto contenido en cuarzo y escasez de minerales m?ficos y c?lcicos, con textura de tendencia panalotriomorfa y fuerte entrelazado cuarzofeldesp?tico; 2) geoqu?micos, con altos contenidos en s?lice; y 3) f?sicomec?nicos, con valores bajos de porosidad (0,75-0,86%) y de los coeficientes de absorci?n capilar y de imbibici?n. La utilizaci?n en los monumentos de Salamanca se ha producido de manera continuada, aunque desigual, a lo largo de m?s de 400 a?os (1515-1932), distingui?ndose tres per?odos: 1) inicial, con Juan de ?lava como probable introductor e impulsor de la piedra; 2) ?lgido, relacionado con la reconstrucci?n de la Catedral Nueva a ra?z del terremoto de Lisboa (1755), as? como con la construcci?n de importantes edificios neocl?sicos; y 3) per?odo de utilizaci?n funcional, destin?ndose la piedra al basamento de los nuevos edificios de finales del XIX y comienzos del XX. La dureza de la piedra se refleja tambi?n en su utilizaci?n para el enlosado, escalinatas y como material de restauraci?n durante el per?odo funcional. Los bloques de reposici?n se reconocen con arreglo a diversos criterios, tales como restos de cu?as abandonadas, heterogeneidad en los tipos de bloques, desajustes en las hiladas y documentaci?n fotogr?fica antigua. Tambi?n se constata un interesante papel est?tico, probablemente derivado de su textura homog?nea y equigranular de visu, sin enclaves m?ficos, y car?cter leucocr?tico. Estos aspectos confieren una percepci?n de piedra discreta, limpia y sin m?cula, que son cualidades acordes con determinadas exigencias de monumentos renacentistas y neocl?sicos, as? como para las restauraciones antiguas de los monumentos platerescos.