Paper Number: 4264
Estremoz Marble: a nomination for ‘Global Heritage Stone Resource’ from Portugal
Lopes, L.1, Martins, R.2
1 Universidade de Évora, E.C.T., Dept. Geociências; Instituto de Ciências da Terra (ICT); Associação Valorpedra – Portuguese Natural Stone Cluster, Portugal. lopes@uevora.pt
2 Universidade de Évora, E.C.T., Dept. Geociências, Portugal
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Historically, the Estremoz marbles from Portugal have been quarried, as ornamental and raw material stone, in Alentejo’s South Portugal District at least since 370 BC [1]. The Cambrian age marbles represents 13% outcrops of the Estremoz Anticline, a Variscan structure with Precambrian core and younger rocks aged Devonian Period [2,3]. The marbles occupy an intermediate stratigraphic position in the Volcano Sedimentary Sequence. The Variscan Orogeny was performed twice under ductile and brittle tension fields so, geological features imprinted in the marbles are beautiful aesthetic patterns highlighted when used as Dimension Stone (Figure 1).
Figure 1: Slab sawed perpendicular to principal metamorphic orientation showing two fold interference patterns.
Considered as a noble raw material since ever, the use of the Estremoz marble still is a symbol of economic strength, good taste and distinction. There is no city in Portugal where Estremoz Marble has not, somehow, been used in both small works of art or utilitarian objects as public monuments and in private homes. It is estimated there would be hundreds of thousands of buildings that have used Estremoz Marble [2]. Pieces of art made with Estremoz Marbles were exported abroad and can be found in Museums and Archaeological Sites throughout Europe and North Africa countries [4]. Today Estremoz Marble’s production can be found all over the World. It may be said that marble based built heritage is omnipresent everywhere in Portugal. Under de “Estremoz Marble” nomination there are several varieties of stones, from pure white to dark blue colors, with or without stripes and veins. The most valuable and distinctive are the light pink varieties called “Rosa Aurora” and “Rosa Portugal”, among others commercial names givem by producers companies.
The historical and widespread application of these marbles in National and International Monuments, some of them already part of the UNESCO World Heritage Sites, is a condition to propose them as Global Heritage Stone Resource for their international recognition.
References:
[1] Alarcão, J. & Tavares, A. 1989. A Roman Marble Quarry in
Portugal. In: Curtis, R. (eds) Studia Pompeiana and Classica in honor of
W. F. Jashemski. New Rochelle, New York, 1–12.
[2] Lopes, L. & Martins, R. 2014. Global Heritage Stone: Estremoz Marbles, Portugal. From: Pereira, D., Marker, B. R., Kramar, S., Cooper, B. J. & Schouenborg, B. E. (eds) Global Heritage Stone: Towards International Recognition of Building and Ornamental Stones. GSL, Special Publications, 407, http://dx.doi.org/10.1144/SP407.10
[3] Pereira, M. F., Solá, R., Chichorro, M., Lopes, L., Gerdes, A. & Silva, J. B. 2012. North-Gondwana assembly, break-up and paleogeography: U–Pb isotope evidence from detrital and igneous zircons of Ediacaran and Cambrian rocks of SW Iberia. Gondwana Research, 22, 866–881, http://dx.doi.org/10.1016/j.gr.2012.02.010
[4] Taelman, D., Elburg, M., Smet, I., De Paepe, P., Lopes, L., Vanhaecke, F. & Vermeulen, F. 2013. Roman Marble from Lusitania: petrographic and geochemical characterization. Journal of Archaeological Science, 40, 2227–2236, ISSN 0305-4403, http://dx.doi.org/10.1016/j.jas.2012.12.030
Este trabalho é co-financiado pela União Europeia através do Fundo Europeu de Desenvolvimento Regional, enquadrado no COMPETE 2020 (Programa Operacional da Competitividade e Internacionalização) através do projeto ICT (UID/GEO/04683/2013) com a referência POCI-01-0145-FEDER-007690.