Slippery Rock Gazette

Bob Murrell 

M3 Technologies

Photos by Bob Murrell

Above: Majestic Stone Soap is used to maintain on this high honed institutional terrazzo floor.

Above: These beautiful but severely etched Tennessee marble café table tops need honing and polishing with 220g, 400g and 800g diamonds, followed with Majestic 5X to restore the finish.

Above: Corian countertops after maintenance polishing with Majestic Stone Plus.

Above: High-traffic terrazo can be challenging to keep pristine. A regular maintenance program is key.

Natural stone conveys the upscale image that corporate management teams want. Stone represents that feel of solidity, perpetual beauty and warmth. For these reasons, these and other similar hard surfaces are being installed at exponential rates. 

There are literally billions of square feet of marble, granite, slate, terrazzo, decorative concrete, and other hard surfaces. This means that there is ample opportunity for cleaning contractors to specialize in these surfaces, as well as their conventional cleaning programs. Hard surface programs generally lend to higher profit margins, which is a welcome sight in today’s competitive marketplace.

All natural stone used as a building material requires knowledge of proper long-term protection, maintenance, and restoration to receive the full benefit from the investment. Lack of knowledge can become an expensive practice. It is imperative in today’s market that retail store operators, building owners, and contract cleaners know what type of natural stone surfaces they are responsible for and the appropriate methods to ensure their lasting beauty and durability. The responsibility to teach and inform these people is that of the suppliers, installers, fabricators, and restoration professionals throughout the stone-related industry.

The first step is to contact a reputable distributor of quality products and technical support who can actually help with the design of a stone-care program. Look in trade publications, search the Internet, or contact a marble supplier to help locate a distributor you can count on for a long-term relationship.

When designing a maintenance program or before attempting a restoration project, it is necessary to determine the type of stone in question. Is it marble, limestone, granite, slate, terrazzo, or some other stone surface? Stones that contain calcium are polished differently than stones that do not contain calcium. We can therefore group stones into two classifications, those that contain calcium and those that do not. Stones such as marble, limestone, terrazzo and concrete all contain calcium and are sensitive to acidic materials. Acids attack calcium-containing stones and etch the surface. If the surface is polished, the acid etch is more noticeable than with textured or honed surfaces. Providing that there are no coatings on the surface of the stone in question, a simple acid test may be all that is required to determine whether the stone contains calcium or not. Simply place a drop of hydrochloric acid (muriatic or phosphoric acid will work, as well) in an inconspicuous area and observe the reaction. If the drop fizzes (effervesces), the stone contains calcium. If there is no reaction, the stone does not contain calcium (or has very little) and is probably granite, slate, sandstone, engineered stone or Corian, or quite possibly some type of ceramic tile or super-dense material made to look like natural stone.

Next, determine what the expected results should be of the material in question. Is a highly polished surface desirable? Is slip resistance a major concern? Don’t forget economics and ease of maintenance. What was the original intent of the design? All of these issues should be of concern when designing a maintenance program for natural stone. 

There are three basic types of stone surfaces: 1) polished; 2) honed; and  3) textured. 

Many times I have seen a honed (smooth finish with little or no light reflection) limestone floor where management insisted on a high gloss appearance. The only way this was possible was to use a topical finish to achieve the look they thought the stone should present. This usually results in failure both with respect to the expected appearance and cost. It could also be detrimental to the integrity of the stone. 

Through years of experience and technical evaluation it has been found that, in most all situations, it is always much easier and more cost effective with better results in appearance to maintain the stone in its original condition, rather than adding a coating to the surface. 

My rules of thumb:

1. Never try to make a stone something it is not;
2. Whatever finish is desired, it should not be poured on top from a bottle; and, 
3. Realize that stone is a product of nature and is admired for its inconsistencies and imperfections. These random patterns are what makes marble and other natural stones so desirable.  

Maintenance on calcium-containing stones and non-calcium- containing stones is identical except with respect to re-polishing. Marble is normally a softer material than most granite and therefore develops wear patterns faster. And because it contains calcium, marble is also more susceptible to chemical attack. However, it is also much easier to restore the polish to marble than to granite. Because marble will etch, we can actually use specific types of acid to aid in the polishing step the same way it is done at fabrication plants worldwide. Superfine abrasives mixed with either potassium oxalate or oxalic acid will polish most marble, limestone, and terrazzo very quickly and efficiently. These compounds and powders are available in ready-to-use formulas (Majestic 5X, Majestic Marble Polishing Compound, Majestic XXX Shine) and can be used with conventional equipment to restore traffic lanes and areas where the natural polish has been degraded. When the floor has deteriorated to a point where powders and compounds no longer work effectively, it will probably be necessary to have the installation restored mechanically.   

Granite-Specific Maintenance

Granite polishing compounds (Majestic Granite Polishing Powder in both light and dark, Granite Polishing Compound, and Granite Gloss) are also available, but since granite is acid resistant, these compounds do not have the advantage of an acid to help expedite the process. Therefore, granite must be polished mechanically using only these superfine micro abrasives in combination with #0 steel wool and sometimes Majestic Marble Crystallizer (used as the lubricant, instead of water). It is a very slow process compared to the re-polishing of marble, and normally requires a step or two of honing prior to polishing.  

One of the most desirable traits of natural stone is that, in most situations, it is completely restorable. A mechanically restored floor is actually more valuable and desirable than a newly installed floor. A properly restored floor has no lippage (uneven tiles), looks better, and is easier to clean. Because it is easier to keep clean, polished surfaces will last longer with less frequency of re-polishing required. All stone flooring in Europe is ground flat when it is installed for these reasons.

Mechanical restoration projects, in most situations, are best left to professionals. With improved diamond technology and equipment, restoration projects are much quicker than those of 20 years ago. Restoration projects should be amortized over at least a five year period when justifying the cost. Maintenance costs will go down, appearance levels will go up, and trip hazards will decrease. All of these factors must be calculated in the cost.

Porosity and Impregnators

All natural stone has a porosity factor. Some stones absorb stains faster than others do, but it is recommended that all stone surfaces be treated with an impregnating sealer. Use of a high quality impregnator, like the Majestic Low Odor Solvent Based Impregnator, can only help an installation by facilitating much easier and more cost effective, long-term maintenance. 

Soiling and staining are much easier to remove, and etching is much easier to restore on marble that has been impregnated. Unlike topical coatings, true impregnators will not appreciably affect the natural qualities of the stone. The original permeability of the stone can remain as high as 97 percent when impregnated with a top quality product, and the appearance of the stone should not be affected. An impregnator can be chosen for its water resistance or water, grease and oil resistance. This is a highly advisable but optional step, and definitely a win/win choice.

Use of a quality stone soap, like the Majestic Stone Soap, is probably the most important part of any natural stone-care program. A good stone soap will actually clean and enrich natural stone, rendering it more soil and stain resistant while keeping the natural colors bright and vivid. This is especially true for honed and textured materials. For polished stones, especially darker materials, it is recommended to maintain with a high-quality, neutral pH cleaner like the Majestic No-Rinse Neutral Cleaner, which contains optical brighteners and does not streak. Be aware that stone soaps might leave a film on highly-polished dark surfaces.      

A periodic intensive cleaning is recommended on a quarterly basis for commercial situations. Use of the Majestic Deep Cleaning Stripper / Degreaser will clean the stone and grout lines of any stone soap and foreign contaminant accumulation. This is very necessary, as a stone soap is a no-rinse product, and dirt tends to accumulate in the grout lines even with the best maintenance program in place. This intensive cleaner should also be used for extremely dirty situations. Using a soft, multi-level brush will definitely help the effectiveness of cleaners.

Other products are also available for countertops, vanities, and vertical surfaces. Majestic has several products which can help in this area, like the RTU No-Rinse Neutral Cleaner, Stone Plus, or Conditioning Treatment and Polish, just to name a few. This is where the importance of establishing a good relationship with a reputable distributor of products and technical support comes into play. There will be circumstances that arise where other specialty products may be needed, such as stain removal poultices, adhesives for repair, and equipment. It is best to find a distributor who understands and supplies products to all phases of the stone industry. Even with the best of maintenance programs in place, there will be special situations that require some thought and expertise. Impregnators and stone soaps do not make stone bulletproof.

Bob Murrell has worked in the natural stone industry for over 40 years and is well known for his expertise in natural stone, tile and decorative concrete restoration and maintenance. He helped develop some of the main products and processes which revolutionized the industry, and is currently the Director of Operations for M3 Technologies.