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Portugal produces a great diversity of ornamental stones. Besides the internationally known white and pink marbles, also light cream limestones are produced, as well as grey, yellow and pink granites, and dark grey slates. From these, limestones are the most request variety today, especially by the Chinese market. Resumo Portugal é produtor de uma grande variedade de rochas ornamentais. Para além das variedades de mármore branco e rosado que são, desde há muito, internacionalmente conhecidas, também se produzem calcários de cor creme, granitos cinzentos, amarelos e rosados, bem como xistos cinzento escuros. Atualmente, a produção nacional centra-se nas variedades de calcário, as quais são muito requisitadas pelo mercado chinês.

The use of many materials of geological origin and recycled materials in the construction of buildings faces an increasing demand and stricter regulation for quality control. Construction products are requested to meet safety standards including those for radon exhalation and gamma radiation emission, amongst other dangerous substances, because if unchecked they could deteriorate the quality and safety of the indoor environment. Construction products shall pass testing for radioactivity in order to meet those standards and to maintain a high ranking position in the international markets.

This work presents the main Portuguese productive areas of ornamental limestones in terms of geographical and geological setting, main commercial types and global resources. They are the Serra do Sicó, Maciço Calcário Estremenho, North of Lisbon – Pêro Pinheiro and the Algarve Basin. A distinction is made between ornamental limestones and marbles because it expresses a marked differentiation on the physical and mechanical properties of both types of rocks. In terms of the ornamental systematics the Portuguese ornamental limestones can be grouped according to their colour and physics-mechanics characteristics. Chemical and mineralogical features reveal a high degree of purity. On account of the detailed geological studies made by Instituto Geológico e Mineiro on the present day main exploitation centres, Portugal as a large potential for ornamental limestones. In addition, the large extensive outcrops in Maciço Calcário Estremenho and Serra de Sicó regions further contribute to increase the resources. To correctly evaluate such potential it is necessary to carry out detailed thematic geological studies, as they are the basis for a sound rationale development of this activity.

The Portuguese territory has many rich in Li-rich mineral occurrences that are mainly associated with aplite-pegmatite dykes and sills intruded in granitic and metasedimentary rocks of the Central Iberian and Galicia – Trás-os-Montes geotectonic zones. Some of those occurrences have a higher economic potencial value, as is the case of the Gonçalo region in the Guarda district and the Barroso-Alvão region near Boticas in the Vila Real district. Geological studies carried out by the Geological and Mining Institute of Portugal (IGM) showed this areas as attractive targets for Li-rich raw material for the ceramic and glass industries of the Iberian market or even for Li-rich standard ore concentrates.