I've been tasked to maintain two family grave sites. Dad used to maintain them but he passed late last year.
The monument company used to do headstone cleaning but doesn't anymore. They recommended using Comet cleanser and water, scrubbing with brush, rinse with water.
I tried the Comet yesterday, scrubbing with a nylon bristle brush. It worked okay but a lot of elbow grease. I used a SS wire brush for stubborn stains on coarser cuts. 3M purple pads worked on smoother cuts but got cut up on coarser surfaces. The wire brush also removed the lichen/ moss on the back of the stones. It looks okay and presentable for now.
Sites online recommended dish soap and water but no harsh cleaners or wire brushes as they may scratch the surfaces.
I'll stick with the Comet cleanser and wire brush for now, as it did work and no damage as I can see.
I may try a brass wire cup brush on a cordless drill with Comet and water in the future for coarser surfaces. I'm not trying to restore the headstones just to maintain them and be presentable.
Anybody have any suggestions how to clean granite headstones?
Thanks
Mercuric acid maybe? Granite is pretty rugged.
http://d2bio.com/
That's what is used by the VA to clean all of the veterans' headstones. As well as *numerous* other historical societies, etc in restoration and preservation. Stuff works *awesome*.
Edit: and I would NOT do a wire brush on a drill, it WILL over time competely destroy the headstone. Stay far, far away. I've seen monuments go to E36 M3 over the course of a year or two from people trying to do that...and it's definitely not a good thing to do. Stiff nylon brush, some assorted nylon brushes. Lots of water and that D/2 cleaner. That is the best way to fly, imo, while doing the least amount / no damage at all.
Edit again: believe it or not the state of IL has a decent guide. And also shows the D/2 I recommend. It's seriously good stuff. Expect it to take a few sessions if it's really bad. But the results ARE night and day over time.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwift_fI1YX4AhUIRDABHYE1CZgQFnoECBYQAQ&url=https%3A%2F%2Fwww2.illinois.gov%2Fdnrhistoric%2FPreserve%2FCemetery%2FDocuments%2FCleaning%2520Grave%2520Markers.pdf&usg=AOvVaw047gEKuUBYS43FDou_9op1
preach (dudeist priest) said:
Mercuric acid maybe? Granite is pretty rugged.
Please, no. Also stay away from bleach. They do WAY more harm than good and leech into the porous material and WILL keep eating it away. It's.. not good.
What are you trying to clean? Just plain old dirt, or is it moss, lichen, or something else?
stuart in mn said:
What are you trying to clean? Just plain old dirt, or is it moss, lichen, or something else?
The smoothest surfaces of the base pad and perimeter of the face could clean up with soap and water. Areas of lettering were a little coarser and collected dirt. The coarsest surfaces collected water and dirt and were black like on gray stone and highly noticeable, the top, sides and backs. Stones are wedge shaped. Lichen was on the backs and brushed off dry then scrubbed wet with Comet. All was rinsed with water. I used three gallons of water but could have used five gallons. They look presentable for now.
In reply to GaryC83 :
D/2 looks very promising, that may be the answer.
Thanks.
Would Wet and Forget work? I use it on my brick house, vinyl windows and exterior silicone caulking.
I have used RoundUp on stone and masonry with great success to get rid of biological growth. Just spray it on and wait for it to die. Wait a month or two and just brush it off with a nylon brush.
Dirt is another matter.
