We often say that antique brown granite "never fades." But in the long run,tan brown granite will fade, just time. Special building surfaces, plazas, etc. are also affected by exposure to wind and sun. For example,new tan brown granite will fade after ten days and a half of the sun.
The minerals in granite are mainly composed of feldspar, quartz, mica, pyroxene and hornblende. In the main silicate mineral structure, each silicon ion is surrounded by four oxygen ions to form a silicon tetrahedron. This basic structural unit is quite stable in nature, resistant to acid and alkali, difficult to dissolve, weather resistant, and has no discoloration.
The fading of granite is also different due to the variety of stone. Generally speaking, the darker lighter granite is easy to fade, because the mineral composition of dark (such as black, dark green) granite is mainly pyroxene, hornblende, basic plagioclase, magnetite. Wait. The light-colored tan brown granite are mainly acidic plagioclase, potassium feldspar, biotite, and quartz. antique brown granite generally form underground, with some new tan brown granite forming first and some forming later.
The first form is often a heavier atomic weight, a deeper position, less oxygen supply, and a higher pressure; the latter is the opposite. Therefore, different minerals generally have different formation periods, and the order is roughly: dark mineral: olivine-pyrorite-hornblende-biotite; light-colored mineral: basic plagioclase-acid plagioclase-potassium Stone-quartz. After the minerals formed first are exposed to the surface, secondary changes are likely to occur due to large changes in the environment, while changes in the late formation are less, and quartz is more stable.
In another case, the secondary mineral is more fading than the original antique brown granite mineral. For example, the green and grass green veneer is the main component of the green chlorite. After 5 to 10 years, the color of tan brown granite is also faded, but with the marble. This change is still very weak. The change in color (fading) is also related to the environment. When the acid and alkali content in the air in the industrial area is high, it is easy to change and fade. In addition, the degree of new tan brown granite maintenance is also important.
