State-Wide, NC - How to Clean a Monument

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This file was contributed for use in the USGenWeb Archives by
Eric Kozen

                 HOW TO CLEAN A MONUMENT

The following do’s and don’ts should help you clean your monuments. 
Always keep this in mind that once a monument is damaged...it is 
damaged and there are no do-overs.

Determine the type of stone to be cleaned – marble, granite, slate or 
sandstone.

Evaluate the condition of the stone – look for cracks, see if the 
surface is eroding and appears to be sugary. If these symptoms are 
visible, DO NO CLEAN THE STONE, it will cause more harm than good.

What type of soiling or staining is visible? The most common types are:

-Dirt
-Lichen (green leafy growth)
-Algae (green or black staining)
-Moss

To start cleaning always moisten the monument well with water. It is 
best to clean a monument after a good rain. Never apply any products or 
remove growth from a dry stone.

If a layer of moss or lichen is on the stone, it can be removed gently 
with a plastic or wooden spatula or paint scraper. NEVER USE METAL.

Always consider the gentlest method possible to clean a stone. A soft 
natural bristle brush and toothbrushes for smaller areas are acceptable 
to use. DO NOT USE WIRE BRUSHES, STEEL WOOL OR ABRASIVE SPONGES.

Gently brush the areas to be cleaned and flush with water constantly to 
remove stains and soil. Clean from the BOTTOM UP to prevent streak 
staining.

If a cleaning agent is to be used, proceed with caution and NEVER USE 
FULL STRENGTH. Here are some products that are recommended:

-Ammonia (household variety) with no additives, mixed at one cup 
 ammonia, one cup water. This will help remove some staining on light 
 colored stones.

-D2 (antimicrobial cleaner) can be ordered from www.cathedralstone.com. 
 This is the best and safest product on the market now.

DO NO USE BLEACH, ORANGE CLEANERS, COMET, OR ANY OTHER HOUSEHOLD 
CLEANERS. DO NOT USE MURATIC ACID FOR MASONRY CLEANING. All of these 
products may result in ferrous staining (rust) and all result in the 
deposition of soluble salts.