ROCK HARD is the first step of a synergistic two-step polishing and maintenance program for all types of terrazzo and natural stone. ROCK HARD works to harden the surface of terrazzo, marble and granite. Then, with the use of DIAMOND GLOSS, an easy-to maintain, super high gloss is produced on the surface. Terrazzo (both cementitious and resinous) will be improved with this process. It is recommended for polishing hard marble surfaces (such as serpentine) and most types of granite. It works to form a protective layer at and below the surface. Continued use of this product will increase the density of the surface. This will make the surface more resistant to wear and staining.