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The archaeological site of Almaraz is located in the old part of the city of Almada, in the south shore of Tagus River, region of Lisbon. The excavated findings and the radiocarbon dating of the contexts where these were found show an occupation that can in fact be dated from the 8th to the 7th c. BCE period, thus a very early stage of the Phoenician occupation in the Iberian Peninsula. Numerous amphorae sherds were found at Almaraz. A spectroscopic characterization of those ceramics was made and is presented here, to help us understand if they were produced locally, in Lisbon workshops, or imported. Sixteen sherds representative of the thousands found at Almaraz were studied with the use of non-invasive spectroscopies, namely by crossing information from micro-Raman and X-ray fluorescence emission data. X-ray diffraction experiments were also performed. In spite of the fact that no ceramic kilns were found at Almaraz until now, the results point to two major groups of amphorae of local origin: one which used clays of Miocene origin, found on the southern shores of the Tagus River, very close to the Almaraz site, at Palenca (with quartz, anorthite, diopside and hematite). Another group, remarkably different, made use of clays of Pliocene origin also from the Tagus Estuary, the Fontainhas clay source (where quartz, anorthite, muscovite and hematite were found).

Silves Castle is located in the Algarve, South of Portugal. Archaeological excavations provided numerous remains of the Islamic presence in this area from the 8th to the 13th c., which could be traced back to the Ommiad, Caliphal, Taifa, Almoravid and Almohad periods. The spectroscopic study of the ceramics, enabled us to discuss their provenance and production techniques. A clear difference in the diffraction patterns of the sherds from the Ommiad period (8th to 9th c.), and the Caliphal period (10th–11th c.) was observed, pointing to imported ceramics in both groups, the latter most likely from Medinat al-Zahra. The origin of the Ommiad ceramics still remains controversial. The samples from the Taifa kingdoms (11th c. period) were characterized as Lisbon productions. The blue and white ceramics studied here (12th–13th c.) are most probably the first samples showing the use of cobalt blue onto a white tin oxide layer made in Portugal.