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Stain Removal from Natural Stone

LATEX AND ACRYLIC PAINT STAIN REMOVAL Latex paints tend to remain on the surface, not penetrating the stone. Use a neutral pH commercial methylene chloride based paint remover, clean water and a stiff bristle brush to remove curdled paint. Rinse the surface with water first. POULTICES Properly blended and ready to use poultices and other alternative removal products are available. REMOVING MILDEW STAINS Mildew stains from fungus, algae or other living plants are typ ically black, green, blue orange or blotchy white in color. Rinse the area thoroughly with clean water. Mix a solution of three parts household bleach with one part water and a dash of dishwashing detergent in a spray bottle. Be aware of citric acids in detergents that may cause etching and/or finish damage. Mist the surface until the stain disappears. Rinse surface with clean water and allow to dry. Repeat if necessary. PRECAUTIONS Do not use solvents and waxes/polishes containing color agents, or oils, turpentine, leaded gasoline or kerosene on marble surfaces. Scouring type cleaners, scouring pads and coarse steel wool should not be used for cleaning polished marble surfaces. The scouring action of these will quickly remove polished surfaces from marble. Acids or acidic cleaning agents should never be applied to cal careous stones. Acids quickly etch and remove the polished surface. Mild acids, such as citric acid in fruit juices and vinegar, will also etch polished stone surfaces when they are not readily wiped off. Be aware of citric acids in detergent that may cause etching and/or finish damage. Waxes and finishes requiring high-speed buffers (1,000 to 7,000 rpm) should be avoided on polished stone floors. Most of these materials will not adhere to polished stone until the original polished surface has worn off. Where pieces of stone are lipped higher than adjacent pieces, high-speed buffers may burnish or burn the high corners and edges of marble. Some chemicals may be harmful to health and environment. Please consult manufacturer’s recommendations and carefully read corresponding SDS (Safety Data Sheets). Testing in an in conspicuous area is recommended.

NTCA Reference Manual | 2024 / 2025

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Chapter 6 | Natural Stone Installations