Surface restoration

Crystallization is a process that polishes a surface. It’s used especially to restore surfaces that were originally polished and have lost their shine over time, due to use and to using unsuitable detergents. Crystallization requires chemical substances (fluorosilicates, acids, water) and single-disc machines fitted with specialized pads. The first step is precisely identifying the surface finish, since this process can only be done on originally polished surfaces; matte, brushed, antiqued, and similar surfaces, which don’t reflect light, are mechanically ground instead. Crystallization is most often applied to marble flooring worn down by foot traffic.

Modern crystallization techniques include polishing with powdered oxalic acid (sorrel salt). This process, in a way, replicates the technology used in marble-polishing factory production lines. That’s why the method is widely accepted and commonly used. Before applying it to large surfaces, though, tests are needed, since unwanted effects such as surface discoloration can occur. Buildup can also form on the surface, and this often shows up faster than the effects of crystallization itself.

In practice, once the oxalic acid powder is applied, the calcium carbonate on the surface turns into calcium oxalate, an irreversible transformation. Polishing with specialized pads (e.g. steel wool) brings the surface to the desired level of shine.