Hi,
Q-I have been asked to clean the windows of a new house. Many of the windows contain cement splashes and a solvent I normally use is a product called "Cement off", made by Titan laboratories. This contains Glycolic Acid. The windowsills are white granite. What precautions if any should I use to prevent damging the granite from this product? The product has a Ph of 3.5

A- Hello-Granite is acid resistant inmost cases so the glycolic acid shouldnt etch the stone.

The one acid that will damage granite is hydroflouric acid (hf). You will also want to note that white granites can be extremley porous so check to see what other ingredients are in the product that could cause true staining.

I would make sure that I use a good masking technique to protect the stone anyway just for safety sake.

Stu Rosen