Removing Ink and Dye Stains from Marble
- Procedure code:
- Outdoor Sculpture Manual - Center For Public Buildings
- Last Modified:
The cleaning or removal of stains from stone may involve the use of liquids, detergents or solvents which may run off on adjacent material, discolor the stone or drive the stains deeper into porous stones. Use the products and techniques described here only for the combinations of dirt/stain and stone specified.
- This specification provides guidance on the removal of ink and dye stains from marble by a combination of absorption and bleaching.
- Wine, ink and dyes are generally water or alcohol based. They are readily absorbed into dry stone when they are spilled or applied to the stone. As the water or alcohol base evaporates, the pigment residue is left deposited on and possibly below the surface.
Read "General Project Guidelines" along with this specification. These guidelines should be reviewed prior to performing this procedure and should be followed, when applicable, along with recommendations from the Regional Historic Preservation Officer (RHPO). The guidelines cover the following sections:
- Safety Precautions
- Historic Structures Precautions
- Quality Assurance
- Delivery, Storage and Handling
- Project/Site Conditions
- Sequencing and Scheduling
- General Protection (Surface and Surrounding)
- "Marble: Characteristics, Uses and Problems"
- "Removing Unknown Stains from Marble Using a Poultice"
NOTE: Chemical products are sometimes sold under a common name. This usually means that the substance is not as pure as the same chemical sold under its chemical name. The grade of purity of common name substances, however, is usually adequate for stain removal work, and these products should be purchased when available, as they tend to be less expensive. Common names are indicated below by an asterisk (*).
Methyl Alcohol (CH3OH):
- Other chemical or common names include Carbinol; Methanol; Methyl hydrate; Methyl hydroxide; Methylic alcohol; Colonial spirits*; Columnian spirits*; Green wood spirits*; Manhattan spirits*; Pyroligneous spirit*; Pyroxylic spirit*; Standard wood spirits*; Wood alcohol*; Wood naphtha*; Wood spirit*.
- Potential Hazards: TOXIC AND FLAMMABLE.
- Available from automotive supply distributor, chemical supply house, dry cleaning supply distributor, drugstore or pharmaceutical supply distributor, hardware store, paint store, or photographic supply distributor (not camera shop).
Ethyl Alcohol (C2H5OH):
- Other chemical or common names include Ethanol; Ethyl hydroxide; Ethylic alcohol; Methyl carbinol; Cologne spirits*; Fermentation alcohol*; Grain alcohol*; proof spirit*; Rectified spirit*; Spirits of wine*.
- Potential Hazards: FLAMMABLE.
- Available from chemical supply house, hardware store or liquor store.
- Denatured alcohol, which carries no liquor tax, should be a satisfactory substitute for ethyl alcohol for stain removing purposes.
Hydrogen Peroxide (H202):
- An unstable compound used especially as an oxidizing and bleaching agent, an antiseptic, and a propellant.
- Other chemical or common names include Peroxide of hydrogen*; Solution of hydrogen dioxide*; Superoxol*; (hydrogen peroxide is commonly sold as a 3% solution; Superoxol is a 30% solution; Superoxol causes flesh burns; 3% hydrogen peroxide does not).
- Potential Hazards: TOXIC (when concentrated); CORROSIVE TO FLESH (gasoline, kerosene and mineral spirits are each a mixture of compounds from petroleum, all of which fall within a specified range of properties); FLAMMABLE (in high concentration).
- Available from chemical supply house, drugstore, pharmaceutical supply distributor, or hardware store.
- Ammonium Hydroxide (NH5O):
CAUTION: DO NOT MIX AMMONIA WITH CHLORINE BLEACHES, A POISONOUS GAS WILL RESULT! DO NOT USE BLEACH ON BIRD DROPPINGS.
- A weakly basic compound that is formed when ammonia dissolves in water and that exists only in solution.
- Other chemical or common names include Ammonia water*; Aqua ammonia*; Household ammonia*.
- Potential hazards: TOXIC; MAY IRRITATE THE EYES.
- Available from chemical supply house, grocery store or pharmaceutical supply distributor, or hardware store.
- Filler material such as Kaolin Clay or Fuller's Earth.
- Mineral water.
- Plastic sheeting.
- Clean, dry towels for blotting the cleansed surface.
- Wood or plastic spatula.
- Waterproof container for mixing paste.
- Wooden utensil for stirring the ingredients.
- Masking tape.
Examine the marble surface CAREFULLY to determine the cause of staining before proceeding with any cleaning operation.
3.02 ERECTION, INSTALLATION, APPLICATION
- For ink stains formulated from metallic salts, follow the procedures for removing iron stains from limestone and marble in the specification "Poulticing Rust Stains from Limestone and Marble".
- For non-metallic ink stains, mix methyl or ethyl alcohol with filler material to form a thick paste the consistency of oatmeal.
- Thoroughly rinse the area to be treated with mineral water.
- Using a wooden or plastic spatula, apply the paste to the stained surface in layers no more than 1/4 inch thick. The poultice should extend well beyond the stain to prevent forcing the stain into previously clean stone.
- Cover the poultice with plastic sheeting to prevent it from drying-out too quickly.
- When the paste has dried, remove it from the surface with a wood or plastic spatula.
- Flush the surface with household ammonia.
CAUTION: DO NOT USE MIX BLEACH AND AMMONIA. THIS WILL PRODUCE A TOXIC GAS.
- Thoroughly rinse the clean surface with mineral water, blot with clean dry towels, and allow the stone to dry completely.
- If there is residual staining, repeat the treatment to achieve the desired level of cleanliness.
Apply a bleach poultice containing a 6% solution of hydrogen peroxide mixed with filler material. Follow procedures C. through G. above.
NOTE: DO NOT USE BLEACH ON DARK COLORED STONES AS THIS WILL CAUSE THE STONE TO LIGHTEN.
END OF SECTION