Discoloration and organic matter pollution of stone

Discoloration
Stone discoloration mainly occurs in stone varieties with poor chemical stability. Here we discuss the dark color of light-colored stone in the dry hanging process where the indoor is not exposed to ultraviolet radiation. A typical case is that the off-white cave stone (travertine) gradually turns yellow from top to bottom during the installation process, and the whole wall turns yellow over time. The chemical stability of travertine itself is poor. Carbon dioxide, sulfur dioxide and nitrogen oxide in the air will react with calcium oxide in the travertine, especially the generated sulfide must be white stone turning yellow. Moreover, during the construction process, the paint and binder contain a large amount of volatile components, which will also react with the stone and have an impact on this kind of stone with poor chemical stability.
Organic matter pollution
After the stone is polluted by organic matter, the color of the polluted part will be deepened and will not fade for a long time, and it will absorb dust. Organic pollutants mainly come from oil pollution and animal contact, especially where people often touch with their hands. In fact, it is often in the most conspicuous place, the place where the decorative stone is the most delicate, and also the place where human contact is the most close. For example, stair handrail is generally decorated with special-shaped high-grade marble. The most inappropriate thing is to use white marble sculpture products as decoration in public places. The situation of this material after being polluted in such an environment can be imagined.
Poor organic joint sealant will also cause pollution of dry-hanging stone curtain wall. On the one hand, it will contaminate the edge of stone plate, and on the other hand, it will absorb dust in the air