The “Alpalhão Granite” (Alentejo, Portugal) as a Potential Ornamental Stone

Abstract:

“Alpalhão granite”, also called SPI, is used as a high quality ornamental stone for interior and exterior applications. It is fine grained and equigranular, and has disseminated feldspar phenocrysts showing a homogeneous bluish grey colour. The SPI was mapped and scanlines (14) and drill cores (4) were carried out for lithofacies and joints characterization, besides petrographical study. Three of the 5 granite outcrops were studied regarding their potential for ornamental blocks exploitation (Carvalhal, Pinheiral and Ribeira de Sor). The Carvalhal area has generally no potential, due to intense fracturing and frequent heterogeneities except for drill core SCA1 area. The Pinheiral area has been exploited in all its extent, but still assures 368,800m3 estimated resources of good granite at depth. Ribeira de Sor area presents a good potentiality for commercial blocks in the eastern zone and a limited potential in the western area due to subsurface fracturing and chromatic changes.

• Periodical: Key Engineering Materials (Volume 548)
• Pages: 20-30
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.548.20
• Online since: April 2013
• Authors: Jose V. Lisboa, Jorge M.F. Carvalho, Rui P. Sardinha
• Keywords: Drill Core, Fracturing, Granite, Joint Spacing, Resource

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