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Gravestones are carved stones use as a memorial remembrance of a loved one. They are placed next to or above the gravesite and are made from a variety of stones such as sandstone, limestone or marble. Gravestones often weather and become prey to moss or lichen because they are subjected to the elements and not cleaned and cared for often. You should clear moss from gravestones once every 18 months to keep them free from stains and help maintain the integrity of the stone.

Clip any high grass or foliage with gardening shears that is interfering with your full view of the gravestone. Remove any trash or clippings to a garbage bag.

Use a soft, natural brush or natural sea sponge to gently brush off any bird droppings or excess soiling. If you are cleaning a flat stone, surround the gravestone with towels to keep dirty water from leaking back onto the stone when you rinse it.

Douse the entire stone with distilled water, making sure to fully saturate it. Allow the moisture to seep into the stone for a few minutes. Distilled water has no chemical or minerals in it and will not react with the properties of the stone.

Fill a bucket with clean distilled water. Dip a natural sea sponge into the water and squeeze it out over the stone as many times as needed to make it well saturated.

Take a dowel that is angled on both sides, or fashion a similar tool from a craft stick or other small wooden device. Scrape against the stone with the dowel, removing as much moss from the headstone as you can. Wet the stone with the sponge as you work.

Rinse the stone with distilled water. Spray a cleaning solution of 1/2 oz. of a pH-neutral product, such as Kodak's Photo-Flo, to 1 quart of distilled water. Saturate the entire stone surface with the spray.

Use a soft, natural brush and work over the area in small circular motions to dislodge any remaining moss residue. Rinse the stone with clean water as you work once you have dislodged a good portion of the moss. Repeat as needed until the moss is removed. Do not allow the Photo-Flo solution to dry on the gravestone.

Perform a final rinse on the stone, heavily saturating it four to six times to remove any remaining residue from the spray cleaner.

Sop up any excess water from the surface of the gravestone with clean terrycloth towels. It is important not to use towels that have fabric conditioners on them, as this impedes absorption and can leave chemical traces on the stone.