Cleaning & Protection of Slate

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Care & Precautions

Use coasters under all glasses, particularly those containing alcohol or citric juices. Many common foods and drinks contain acids that will etch or dull the surface of many stones.

Do not place hot items directly on the stone surface. Use trivets or mats under hot dishes and placemats under china,  ceramics, silver or other objects that can scratch the surface.

Spills & Stains

In the occurrence of a spill immediately blot, not wipe, the area with paper towel. Proceed with flushing the area with plain water and mild soap and rinse several times. Dry the area thoroughly with a soft cloth. Repeat if necessary. If the stain does not lift, refer to the following section, stain removal.

Stain removal - Identifying the type of stain is important when determining what type of methods will be used to remove it.

Surface stains can generally be removed by using the appropriate cleaning product or household chemical. Penetrated or stubborn stains may require using a poultice or calling a professional. The following sections identify various stains and a recommended procedure as well as the preparation and application of the poultice removal technique.

Types of Stains & Cleaning Applications

Oil based - (grease, tar, cooking oil, milk, cosmetics) An oil-based stain will darken the stone thus, it is recommended to chemically dissolve the stain and the flushed or rinsed away. Clean gently with a soft liquid cleanser containing bleach, a household detergent, ammonia, mineral spirits or acetone.

Organic - (coffee, tea, fruit, tobacco, paper, food, urine, leaves, bark, bird droppings) May cause a pinkish-brown stain which may dissolve once the source has been removed. If outdoors, the sun and rain regularly bleaches out the stains. If indoors, use a 12% hydrogen peroxide (hair bleaching strength) with a few drops of ammonia. 

Metal - (iron, rust, copper, bronze, brass) Iron or rust stains are orange to brown in color and follow the shape of the staining object. Copper, bronze or brass stains are green or muddy brown and are the result of exposure to moisture. Using a poultice removes metal stains, but deeply penetrated rust stains are extremely difficult to remove if not impossible.

Biological- (algae, mildew, lichens, moss and fungi) Due to the biological composition, a dilution of 1/2 cup of ammonia, bleach or hydrogen peroxide, will remove the stain. NOTE: DO NOT MIX BLEACH AND AMMONIA. THIS COMBINATION CREATES A TOXIC AND LETHAL GAS

Ink - (magic marker, pen) Light colored stone: use bleach or hydrogen peroxide. Dark colored stone: use lacquer thinner or acetone.

Paint - Latex and acrylic paints will not cause staining unlike oil-based paints, Linseed oil, putty, caulk and sealant (refer to oil-based stains section). Use lacquer thinner to gradually remove the paint or a razor blade and carefully scrape it off. Large amounts should be removed with a commercial stripper available at a hardware store or paint store. It is important to note that paint strippers can etch the surface of the stone and re-polishing may be necessary.

Water spots & Rings - (surface accumulation of hard water) Buff with dry 0000 steel wool.

Fire & Smoke Damage - Smoke or fire stained fireplaces and stones may require a thorough cleaning to restore the original appearance. Smoke remover products may save time and effort.

Etch Marks - If an acid or acid based product is left on the surface of the stone it may either etch or etch and stain the stone. Once the stain is identified and removed, wet the surface with water and sprinkle marble polishing powder , available at hardware store or stone dealer. Using a damp cloth, rub the powder into the stone in a circular motion or use a buffing pad with a low speed power drill. Continue to buff until the etch marks disappears and the stone surface shines. If having difficulty contact your stone dealer.

Scratches & Nicks - Surface scratches may be buffed out with dry 0000 steel wool, deeper scratches and nicks should be repaired and re-polished by a professional.

Natural Stone Do's & Don'ts

• Do dust mop floors frequently

• Do clean surfaces with mild detergent or stone soap, then thoroughly rinse and dry the surface 

• Do blot up spills immediately

• Do protect stone floor with a non-slip mats or area rugs and countertop surfaces with coasters, trivets or placemats

• Don't use vinegar, lemon juice or bathroom, grout, or tub and tile cleaners on marble, limestone, travertine or onyx surfaces.

• Don't use dry or soft abrasive cleansers

• Don't mix chemicals unless specifically instructed to do so

Reference: Marble Institute of America

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