The natural stone you have in your home, office is an investment that will give you many years of beautiful service. Simple care and maintenance will help preserve your stone’s beauty for generations to come. This post has been transcribed from the Natural Stone Institute to present routine cleaning guidelines as well as procedures for stain removal should it become necessary. All methods of cleaning should be in accordance with ASTM C1515-01.
Cleaning Do’s and Don’ts
When discussing care and cleaning procedures with your maintenance staff, there are recommended do’s and don’ts that should always be followed:
Do clean surfaces with mild detergent or stone soap. Do thoroughly rinse and dry the surface with clean, clear water after washing. Do blot up spills immediately. Do protect floor surfaces with non-slip mats or area rugs and countertop surfaces with coasters, trivets, or placemats.
Don’t use vinegar, lemon juice, or other cleaners containing acids on marble, limestone, travertine, or onyx surfaces. Don’t use cleaners that contain acid such as bath- room cleaners, grout cleaners, or tub & tile cleaners. Don’t use abrasive cleaners such as dry cleansers or soft cleansers. Don’t mix bleach and ammonia; this combination cre- ates a toxic and lethal gas. Don’t ever mix chemicals together unless directions specifically instruct you to do so. Don’t use vacuum cleaners that are worn. The metal or plastic attachments or the wheels may scratch the stone’s surface.
Daily Cleaning Procedures and Recommendations
Clean stone surfaces with a few drops of neutral cleaner, stone soap, or a mild liquid dishwashing detergent and warm water.
Use a clean soft cloth for best results.
Too much cleaner or soap may leave a film and cause streaks.
Do not use products that contain lemon, vinegar, or other acids on marble or dolomite.
Rinse the surface thoroughly after washing with the soap solution and dry with a soft cloth.
Do not use scouring powders or creams; these products contain abrasives that may scratch the surface.
General Guidelines for Stain Removal
1. Remove any loose debris.
2. Blot spills; wiping the area will spread the spill.
3. Flush the area with plain water and mild soap and rinse several times.
4. Dry the area thoroughly with a soft cloth.
5. Repeat as necessary.
6. If the stain remains, refer to the section in this guide on stain removal with poultice.
Identifying & Removing Stains
Oil-Based Stains (grease, cooking oil, cosmetics)
Will darken the stone and normally must be chemically dissolved so the stain’s source can be rinsed away. Clean gently with a soft liquid cleanser, household detergent, ammonia, mineral spirits, or acetone.
Organic Stains (coffee, tea, fruit)
May cause a pinkish-brown stain and may disappear after the source of the stain has been removed. Outdoors, with the sources removed, normal sun and rain action will generally bleach out the stains.
Indoors, clean with 12% hydrogen peroxide and a few drops of ammonia.
Inorganic (rust, copper, bronze)
Inorganic Metal Stains (iron, rust, copper, bronze) - Iron or rust stains are orange to brown in color and leave the shape of the staining object, such as nails, bolts, screws, cans, flowerpots, or metal furniture. Copper and bronze stains appear as green or muddy brown and result from the action of moisture on nearby or embedded bronze, copper, or brass items. Metal stains must be removed with a poultice.
Deep-seated, rusty stains are extremely difficult to remove and the stone may be permanently stained.
Ink Stains (magic marker, pen, ink)
Clean light colored stones with bleach or hydrogen peroxide.
Use lacquer thinner or acetone for dark-colored stones.
Paint Stains
Small amounts can be removed with lacquer thinner or scraped off carefully with a razor blade.
Heavy paint coverage should be removed with a commercial liquid paint stripper.
DO NOT USE ACIDS OR FLAME TOOLS TO STRIP PAINT FROM STONE.
Water Spots and Rings (surface accumulation of hard water)
Buff with dry 0000 steel wool.
Using Stain-Removing Poultices
New technologies for sealing and impregnating stones are making it harder and harder to stain your natural stone. However, if your countertop was installed years ago and it was stained, there is a simple way to fix this problem: a poultice is a liquid cleaner or chemical mixed with a white absorbent material to form a paste about the consistency of peanut butter that "absorbs" the element that has penetrated the stone.
Applying the Poultice Prepare the poultice.
If using powder, mix the cleaning agent or chemical to a thick paste the consistency of peanut butter.
If using paper, soak in the chemical and let drain.
Don't let the liquid drip. Wet the stained area with distilled water. Apply the poultice to the stained area about 1/4 to 1/2 inch thick and extend the poultice beyond the stained area by about one inch.
Use a wood or plastic scraper to spread the poultice evenly. Cover the poultice with plastic and tape the edges to seal it. Allow the poultice to dry thoroughly, usually about 24 to 48 hours.
The drying process is what pulls the stain out of the stone and into the poultice material.
After about 24 hours, remove the plastic and allow the poultice to dry. Remove the poultice from the stain.
Rinse with distilled water and buff dry with a soft cloth. *Repeat the poultice application if the stain is not removed (It may take more than one application for difficult stains).
Etch Marks
Etch marks are not stains. They are areas where the glossiness of the surface is dimmed. Usually they are visible only by a certain angle. These marks are common on marble but can occur in dolomites too.
To avoid these marks make sure your surface is properly sealed before installation and avoid strong acids and inappropriate cleaning products (check for pH neutrality).
To remove an etch mark is simple: all you will need is an etch remover, water and paper towel.
Start by adding the powder from the etch remover into the stone with wood or plastic scraper.
Add water and use a paper towel to buff it in a circular motion for a couple of minutes.
If necessary, add more ware and continue buffing until the etch mark disappears and the surface shines again. (click here for full video)
HELPFUL TIPS
DO use a cutting board in all kitchen countertop applications DO use coasters or placemats under all glasses, particularly those containing alcohol or citric juices DO use trivets under china, ceramics, silver or other objects that might scratch or scorch the surface DO clean surfaces with mild detergent or stone soap DO thoroughly rinse and dry the surface after washing DO blot up spills immediately
DON'T use vinegar, lemon juice or cleaners containing acids on marble, onyx, limestone or travertine surfaces DON'T use cleaners that contain acid such as bathroom cleaners, grout cleaners or tub and tile cleaners DON'T use abrasive cleaners such as dry cleansers or soft cleansers DON'T mix bleach and ammonia; this combination creates a toxic and lethal gas don’T ever mix chemicals together unless directions specifically instruct you to do so
Source: The Natural Stone Institute
SUGGESTED PRODUCTS
Etch Remover by LUSTO ITALIANO
Removes etch and water marks on marble, travertine, limestone, dolomite & onyx. Not for use on granite.
Countertop Cleaner Spray by DRY TREAT
Ideal Cleaner for Natural Stone - Remove Dirt, Dust, & Oil from Surfaces with a more durable cleaning solution
Stain-proof Premium Impregnating Sealer by DRY TREAT
Ideal Sealer for Natural Stone - Liquid & Stain Repellent for Countertop
Ideal Sealer for Natural Stone - Liquid & Stain Repellent for Countertop (without chemical odor)
Countertop Sealer & Cleaner by FILA
Countertop cleaner for marble, granite, travertine, limestone and quartzite.
