Tests are reported investigating the absorbing properties of 21 limestones and sandstones from different quarries. Comparisons are made with the absorbing properties of bricks. The main conclusions drawn from research are as follows. The absorbing properties of sandstones and limestones with great percentage of calcite (up to 97per thousand) are similar to those bricks (0,10 <ds> 0, 34per thousand). The absorbing capacity of limestones with clay constituents is bigger several times from the absorbing capacity of limestones without contents of clay. The absorbing capacity of silicified limestones increase with the growth of the percentage of silica and is up to 10per thousand.