Professional Advice: Choosing Natural Stone

Lichen, algae, mold and tannins from trees that stain headstones are considered biological contaminants. Lichens roots secrete acid that will dissolve the calcium in marble and limestone. Algae, mold and lichen grow because the stone pores absorb water. Moisture in the stone during the winter months will freeze and thaw causing spalling (surface loosening of minerals and cracking).

Tannins stains are caused from leaves, nuts and bark that have fallen from trees. Headstones can be cleaned with common household ingredients that most of us have (ammonia, liquid dish soap and bleach used separately)……. Note: That this is not what natural stone restoration professionals would use, but, the cost of “not” hiring them may lead to further damage, so this home remedy will help your monument to a love one’s life, live for future generations to come.

Step #1 Soak the stone with clean water with pump sprayer, keeping stone moist for 10-20 min.

Step #2 Spray a solution of 1-cup ammonia, 3-4 tablespoons of dish soap and one gallon of water to the stone, allowing the mixture to dwell on the stones surface 15-30 min. (Reapply to keep moist).
Step #3 Use a soft nylon brush, toothbrush or plastic putty knife to remove contaminants from surface. Reapply solution and lightly scrub with nylon brush and toothbrush from the bottom up. Repeat the process until you think you have all the contaminants removed using this method.
Step #4 Rinse the stone thoroughly with clean water.
Step #5 Make a separate mixture in another pump sprayer of ½ household bleach and ½ clean water. Let the stone dwell with the mixture keeping it moist for 15-30 min. allowing the mixture to dry in the suns rays if possible (let the sun work with the bleach) and rinse thoroughly 1-3 hrs later.

Step #6 Optional is instead of doing the restoration your self is to hire a natural stone restoration professional to clean and seal from future biological contamination and damage.

Cleaning Grave Marker

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