Cleaning and Preservation of Tombstones:
Water and a soft bristle brush (don't ever use a
wire brush or anything metal) is the best way to clean a marker, but
if necessary, only non-ionic detergents should be used for removing dirt, algae, and lichen
from the stone. If the lichen has been stuck on for quite some time, try to gently scrape it off
with a fingernail, plastic scraper, or wood craft stick.
When cleaning a headstone, it is important to never use soap, such as Ivory, or commercial
household detergents, as these solutions are rendered insoluble by calcium ions present in stone
and hard water. Cleaning materials that contain phosphoric acid, such as Lime Away or Naval Jelly,
may stain the marker or leave soluble salts behind.
Do not use products that contain sodium chloride, sodium sulfate, sodium bicarbonate, trisodium
phosphate (Calgon), and ammonium carbonate, as they may form and deposit soluble salts in the
headstone. Clorox (sodium hypochlorite) is not recommended because it turns marble yellow. Borax
(sodium hydroxide) will cause a stone to begin to disintegrate. Calgon contains a number of
additives that may cause the stone to deteriorate.
are available from janitorial and conservation
suppliers. One example, named Photo-Flo,
is available from photography supply stores. Another brand, called Orvus, is available from feed stores and livestock supply
stores in either liquid or cream form. Non-ionic detergents are recommended for gravestones
because they do not contain or contribute to the formation of soluble salts, but aid in the
removal of dirt and lichen.
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