Fading of brick, concrete block, stone, etc.

What people call fading is not an actual change of the materials inherent color. The "fading" appearance is actually some degree of efflorescence in the surface pores. Look very closely with a magnifying glass and you should be able to see that the white powder of efflorescence is what lightens the overall appearance. This is true of concrete block and pavers, clay brick, stucco, all stones, etc.

This includes concrete products. The pigments generally used worldwide to color concrete are "iron oxide minerals" and do not lighten in color from exposure to sunlight. However, this is not true if "organic" pigments (i.e. carbon black) were used as they will become lighter in color over time.

What this means is two things.

• "Fading" of a surface can be prevented from the beginning.
• A "faded" surface can be restored and the "fading" can be prevented from returning.

• The cleaning is easily done as described on the "efflorescence" page in "Problem Solving"

• The prevention is described, with pictures, on the same page. It involves simply choosing one of the Aldon penetrating sealers from the materials page on Surface Types

Another possible cause of patches of whitish staining that might be thought to be fading could be surface mineral deposits left behind by sprinkler water, rain water runoff, etc. You cannot always tell which is the true cause, but fortuntely both efflorescence and surface mineral deposits require the same steps and treatments. See surface mineral deposits in "Problem Solving"

Note:
Sometimes cleaning is a trial and error process. The cause of the problem might be different than thought, or have multiple causes and results that must be handled in steps. In rare cases, it cannot be cleaned. Proceed as though it is an experiment whose results must be evaluated.

Any Aldon cleaner has more than one purpose. It is not limited to only this cleaning project.