Over a period of time memorials will accumulate a layer of deposits resulting from hard water, dust, dirt, lichens, mold or fungus that grow on porous stone. A gravestone should be cleaned and maintained carefully so as to avoid getting it scratched or tarnished.
Before cleaning a memorial you must first evaluate to make certain it is in stable condition with no flaking, cracks or risk of further deterioration from the cleaning process.
Granite and Marble Memorials
When cleaning granite memorials and due to granite’s durability, it is all right to use a more aggressive scrubbing technique.
- natural brushes/tooth brushes
- non-ionic soaps/detergents avoid detergents that contain compounds like sodium bicarbonate, sodium chloride, sodium sulfate, ammonium carbonate, and trisodium phosphate (TSP or Calgon)
- cuttle bone to remove hard water or calcium build-up
Below are items you DO NOT want to use when cleaning memorials as they may cause damage:
- wire bristled brushes or metal instruments
- acid or acidic cleaners
- cleaners/detergents containing compounds like sodium bicarbonate, sodium chloride, sodium sulfate, ammonium carbonate, and trisodium phosphate such as TSP, Calgon, Ivory, Borax, Clorox, Fantastik, Formula 409 (Spic and Span, or any other abrasive cleaner)
- pressure washers
- waxes or sealants of any kind
Bronze markers consist of a bronze plaque mounted to a base usually of granite or concrete. Since bronze markers consist of two components you can utilize the cleaning method for polished granite for cleaning the base.
The bronze plaque is finished with an applied coating to seal and preserve the original appearance. Over time this finish will eventually deteriorate and is accelerated through neglect or improper care.
When cleaning bronze you will need the following items:
- soft cloths, especially for new markers which should only be cleaned
- with a soft, damp cloth to remove top soil and grime
- nylon brush
You can finish with a light application of WD-40 or car wax to put a sheen on the marker and protect it from the elements. When using these to finish the bronze, be sure to carefully cover any granite or marble to avoid staining.
Here are some items you DO NOT want to use or to keep in mind while maintaining your bronze marker:
- brushes, especially wire-bristled brushes or metal instruments on new markers
- steel wool as it may scratch it
- chemicals or oils to new markers (accelerates the breakdown of the protective coating)