Therefore, there will be sufficient reserves to allow the feeding of several plants with clay raw materials for the production, for instance, of construction ceramics shaped both by extrusion and by pressing adequate for distinctive functions (Coroado, 2000).
Composite or blended samples have been prepared in order to find out if these clays could be utilized in the manufacture of high added-value construction ceramics.
Also, the properties of the fired specimens are comparable to those considered appropriate for high to very high quality construction ceramics exhibiting high to very high mechanical bending strength and low to very low water absorption.
The achieved results indicate that the clays from Vila Nova da Rainha are appropriate raw materials to be utilized on the production of construction ceramics of unit values higher than the ones which are proper of traditional hollow bricks.
Clays from Vila Nova da Rainha were found to be suitable for the manufacture of a wide range of construction ceramics characterized for exhibiting high mechanic bending strength values and low water absorption values, properties suitable for the production of extruded floor and wall tiles.
The values of mechanical bending strength (11 MPa) are good to support the mechanical movements involved in the layout of the ceramic products, when compared with the current values found in construction ceramic materials (Grade and Moura, 1985).