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After highlighting the long historical trajectory of Bernardos' slate and its influence in the Spanish historical heritage, Fernando Lopez Mesones (Doctor and Mining Engineer at UPM) emphasizes his singularity and quality in the following chapters about the ARCHITECTURAL VALUE OF THE SLATES OF BERNARDOS.

First, it’s a presentation of the geological setting (chapter 1): the Slate of Bernardos is a metamorphic rock whose geological history dates back to the Precambrian era / 550 million years, and is called "Phyllite" (Lithotype B2) . Due to its chemical composition and schistosity patterns, it is distinguished from lower-grade slate, strictu sensu slate and Mica-schist, with undulating veining, lead-gray color, and rough texture, its hardness and density as well as its very low rate of water absorption.

Chapter 2 recalls the importance of the use of original materials for the restoration of historic monuments (Charter of Athens) and are based on the results of tests corresponding to harmonized European standards, demonstrating the excellent technical properties of the Phyllite of Bernardos and its adequacy to the quality standards in force (Chapter 3).

Then, in Chapter 4, a special mention is made of its energy efficiency (Bernardos Phyllite mitigates the effects of solar radiation), the sustainability of the product (economic, social and environmental aspects) and the LEED Certification (the use of Phyllite of Bernardos contributes to obtaining points allowing to obtain one of the 4 LEED Certificates).

Finally, in chapter 5, 6 and 7 an inventory is made of the many architectural solutions offered by the Phyllite of Bernardos, a noble and exclusive material with unparalleled physical and mechanical qualities: flooring, paving, wall coverings, stonepanels, flagstones, slate for roofing and decorative stones , intended in their different finishes (cleaved, sawn, brushed, flamed, bush-hammered, tumbled) both in historical heritage and in modern architecture: ventilated facades, terraces, laying on plots, interior decoration, landscaping, roofing, renovation.

ARCHITECTURAL VALUE OF THE SLATES OF BERNARDOS

Fernando López González Mesones - Mining Engineering from the Universidad Politécnica de Madrid

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