The Gravettian lithic assemblage from Foz do Medal presents different characteristics when compared with other more “traditional” Gavettian assemblages, namely from Portuguese Estremadura, although sharing some features. The objectives of the reduction and the strategies applied show big peculiarities which can be related mainly with the geological context and the raw material sources. The scarcity of biogenic chert and the availability of other local siliceous rocks such as hydrothermal cherts, rock crystal and other types of fine quartz, have played a major role in the choices made by prehistoric humans. Quartz, in its several varieties, was the chosen raw material for knapping, reaching more that 80% of the total collection. As a result, the regional environmental context and human strategies show great variability between Foz do Medal and Côa valley Gravettian assemblages and other Gravettian assemblages where chert is easily available.