This paper presents laboratory analyses of the influence of an acidic environment, salinity and temperature change are able to exert on the geomechanical properties of the opoka-rocks. This rock material, deriving from four sites in East–Central Poland, was found to be variously resistant to factors like the destructive action of water-soluble salts and the effects of an acidic environment, on account of the actuallydiverse nature of the rocks in question. Ultimately, the work offered a basis for a distinction to be drawn between the light opoka-rocks present at the Annopol and KazimierzWielki sites, and the heavy opoka-rocks from Bochotnica and Krasnobród, in terms of both textural and physical-mechanical features. The heavy opoka-rocks from Krasnobród proved least resistant to an acidic environment, which left strength reduced significantly. This kind of rock also experiences both an increase in porosity and absorbability and a decrease in weight. Furthermore, the influence of an acidic environment on aesthetic features of the examined rocks was in all cases negative, salts formed a patina on surfaces that obscured original structural and textural features. None of the tested types of rock presented resistance to the crystallization pressure such salt is able to exert.