Tombstone Cleaning Basics
Post Date: 04 Jun 2009 Viewed: 769
"Enough with the wire brushes! Would you clean your teeth with a wire brush?"
Wire brushes, metal instruments and abrasive pads may give you instant satisfaction but, if you clean with anything that is harder than the stone, you risk scratching the face of the stone and causing more damage in the long run. The same goes for acidic cleaners which includes most household cleaners. Powerwashers are also NOT recommended. Anything that puts out greater than 60 psi is too much force to use on OLD and fragile stones. A garden hose putting out a gentle soaking spray is enough to clean and flush the stone (garden type sprayers also work well).
Stones are composed of minerals and salts. Adding chemicals to them can often cause chemical reactions that will erode the stone faster than if you just left it alone. CGN recommends that you use the following low tech method and consult with us or professionals before using other methods. Remember, we respect our monument dealers but often we are talking OLD gravestones, not the granite that has been used for the past century. Each stone may need its own diagnosis; what is good in one situation is not necessarily good for all.
For marble, limestone and sandstone, use water and soft bristle brushes, natural or nylon . Granted it doesn't sound like a miracle cleaner and it doesn't happen quickly but with some patience and time this will clean most environmental soiling and lichens from stones. Keep the stone wet at all times; really wet. Where a garden hose is not available, be sure to bring plenty of jugs of water and keep dowsing the stone as you work and, most importantly, flush the stone well when done. Scrub the stone from the bottom up to avoid streaking and further staining.
Household ammonia can be used if one can stand the aroma, but again be sure you flush the stone completely, more than one or two times, when you are done. Wearing proper eye protection is also a must.
If lichen is a problem, you can scrape with a wooden or plastic scraper. Tongue blades or craft sticks work well. Also, inexpensive plastic putty scrapers from home stores work well. Remember, no metal.
There are also poulticing techniques that can be used to soften lichen. Many lichens will, once removed, leave a scaring affect on the stone because the waste product they give off is an acid that works with the stone's own salts and chemistry to erode it or bleach out some of its mineral component.