CRPT Spotlight: The Don'ts & Do's of Cleaning Headstones

Ever since we started offering Cemetery Resource Protection Training (CRPT), we field a lot questions about how to care for grave markers themselves.  It's actually a request we love to get, because there's so much advice out there that ultimately causes harm to markers, even if it's trying to help.

Cemeteries and markers are archives of human memory and must be handled with great care.

We'll look at how to best clean a grave marker in just a moment, but first, let's start with what NOT to do.  When recording a grave marker:

• DON'T make rubbings of the stone.  Over time, the pressure and friction speed the wear on the stone itself, gradually rubbing away the parts that stand out.
• DON'T apply shaving cream to the stone--people have tried this to make the letters stand out more, but the stone absorbs the chemicals in shaving cream, and those chemicals eat away at the marker.
• DON'T put flour on the stone either!  This has been offered as a less chemical-intensive way to make letters stand out, but flour actually makes a great environment for plants and moss to grow.  Their roots dig into the stone and cause it to break down.

When cleaning a grave marker:

•  DON'T USE BLEACH.  This is kind of the folk remedy for cleaning headstones that makes us cringe every time we hear it.  We know people do it with the best of intention, and the stone does look pretty and white--at first.  Unfortunately, bleach is a very caustic material.  The salts in bleach soak into the stone (just like with the shaving cream mentioned earlier).  Once they've soaked in, they eat away at the stone itself, producing two kinds of damage: sugaring and an orange tint.  Sugaring is kind of what it sounds like: when the stone starts to erode from bleach salts, it breaks down into tiny particles--I've seen someone gently swipe the top of a bleached stone and come away with a finger covered in white powder.  The orange tint is pretty straightforward too--the areas where a stone has been bleached will eventually take on a bright orange hue.  Neither of these results happen immediately, but they will happen.  Worst of all, there's no way to UN-bleach a stone.  Once the salts have soaked in, there's no removing them.
• DON'T use other household cleaners.  As with the products we've already discussed, stone usually responds poorly to the introduction of chemicals that were never intended for it.
• DON'T use a brush that's harder than the stone.  Using a very stiff-bristled brush, plastic or wire, will scratch the surface of the stone, damaging its integrity and sometimes eroding any legible writing.
• DON'T use high water pressure, even as hard as you could spray from a hose.  It has the same effect as too-stiff brushes, eroding the stone from the outside.
• DON'T use any sealant on stone.  I've fielded questions about how best to seal a grave marker, I think for the purpose of keeping it clean, and the basic answer is that you don't want to seal it at all.  Remember: stone absorbs water, including water in the ground, and the porous nature of the stone allows the water to escape.  If we seal a stone, we leave the water no exit, eventually causing the stone to crack and crumble.

But finally, DON'T despair!  There are simple things that can be done to clean and protect a grave marker.  When documenting a marker:

 

Grave marker in Savannah, Ga.  Image on left is original; image on right simply "autocorrected."

• DO take lots and lots of pictures.  Use sunlight & shade if possible.
• DO bring a mirror!  Sometimes reflecting light onto the stone makes things show up in ways you wouldn't expect.
• DO feel free to adjust those pictures once you get them on a computer.  Changing contrast and lighting levels can work wonders for making an old stone legible.

When cleaning a marker:

Headstone before cleaning.

•  DO clear away any plants growing into the stone by gently clipping them near their base (taking caution not to rip them out of the stone, lest, they cause it to crumble).
• DO use soft brushes and approved substances to gently scrub the stone clean.  You can use D/2, masonRE B+, or even just plain water!
• DO start at the base of the stone to wet, apply cleaner, and scrub, then work your way up.  It seems not to make sense at the outset, but it prevents stone from latching on to the dirt washing down from above, so keeps your cleaning job from looking streaky.
• DO rinse thoroughly at the end to remove any residual dirt.



Working bottom to top using soft brushes, D/2, and water.

• DO feel free to spray with an approved cleaner like D/2 and walk away, if you're short on time.  Even without scrubbing, it absorbs into the stone to kill any biological materials growing on or in it, helping to protect it over time.

DO take pictures before and after (and maybe even a few weeks later if you want to see a more dramatic difference). DO get your community involved!  It can be a great project that both improves preservation at cemeteries and helps to foster a sense of place and past for a local population.  Finally, DO keep us posted--we want to hear about your efforts and continue to help answer any questions.

After

If you would like more information on cemetery and grave marker care, visit Chicora, which has extensive resources on cemetery care and protection.  Their page on cleaning headstones is quite useful, and includes details on use of D/2 as well as information on where to order it.

 For information on masonRE B+, visit the Cathedral Stone website.

Close shot of the side of an obelisk in my own family's cemetery near Piedmont, SC.