Marble why fade?

Marble is very extensive application in the life, although marble long life but in this process will inevitably be fade phenomenon. Now let's go to find out the reason it.

Marble(Marble Slab) mainly calcite, dolomite by such mineral composition, often in the former majority. The calcite molecular formula for CaMg CaCO3, dolomite CO3] [for 2 has CO3] [carbonated roots, it is lively, ion easy and sulfur dioxide function, form air gypsum (Ca [SO4]. In this gypsum 2H2O), muddy waters of the particle shape. The calcite easy and water soluble in water can form of calcium hydrogen carbonate (Ca [HCO3] 2) in water after losing and become to calcium carbonate. After these changes, marble polishing plank original crystal MoGuangMian has ceased to exist, so wall decoration noodles, especially open-air act the role of material unfavorable choose marble is the reason. As the marble wall decoration, by 2 ~ 3 years commonly will talk about change color.