In the quarries of Poio, in Foz-C ô a (NE of Portugal) is exploited a particular slate schist, due to being possible to extract large blocks. The maximum length obtained was of 27m. The average blocks are extracted with 3m in length, although the width and height are usually less than 1m. The quarries of Poio have been exploited, in industrial terms, for about 150 years and in particular for production of shores of vineyards of Porto Wine. Recently, these schists have also been applied in the building industry.
In the present paper the mechanical characterization of those materials is presented from laboratory tests (Point-load test, Uniaxial compression test, Indirect traction – Brazilian test, and Flexural test) and also in situ testing (Windsor probe and Schmidt hammer) in such a way to potentiate constructive solutions of structures with great slenderness and architecturally very interesting.