MELT Calcium Chloride Crystals are not known to chemically attack stone under typical application conditions. However, if the stone is porous, melt water created during deicing may soak into pores or cracks, subjecting the stone to possible freeze-thaw damage. This type of damage is possible under certain conditions because melt water trapped in pores or cracks may re-freeze, creating a large amount of pressure beneath the surface of the stone. If the structure of the stone is not strong enough to withstand this pressure, the stone will flake or powder. This type of damage depends on the porosity and strength of the stone, not on the type of deicer used to melt snow and ice.
 
Because there are many different kinds and grades of stone, Snow Joe cannot predict where damage may or may not occur. Therefore, Snow Joe’s MELT Calcium Chloride Crystals are generally not recommended for applications on masonry (stone, brick and mortar joints)