Below are two links: the top one is to a video that includes clips of a girl wielding a power drill with a hard plastic rotating wheel attached to it as she grinds across the surface of an early pioneer gravestone. Layers of marble are ground away in this process — it just doesn’t peel away the lichens alone. Biological growth will return over time. The inscriptions are polished smooth and reduced in clarity.
Please read the article in the second link “Abrasive Cleaning of Grave Markers” to learn what the real results are after using this power tool and totally unnecessary method.
Your ancestors gravestones are original historical artifacts and should be treated as such!
“NCPTT does not advocate the use of power tools to clean headstones. The use of such tools can abrade and remove granules from weathered marble and limestone. We do not advocate grinding, re-lettering, or polishing headstones as this alters the original surface of the grave marker. The company that makes Nyalox brushes compares their performance to wire brushes, which are much too harsh for a stone surface. Would you use a Nyalox brush on a power drill to clean the surface of your automobile? If not, then you would not use it to clean a grave marker.”