Once the stone type has been identified and any problems corrected or accepted, a daily system should be developed which will keep the stone in a polished condition. The main reason polished stone floors become dull is that we walk on them and “grind” in dust, sand, and other fine, gritty matter that abrades the finish. Remember that it will take three to four times longer to bring the shine back once the floor has gone dull. If allowed to remain dull for a long period it may even have to be refinished to bring back a good reflection and gloss.
Whatever the method used to maintain the shine, polishing a certain amount of the floor each day is best. The only difference will be in how many square feet can be polished with the method being used. With marble and limestone, one person can polish 200 to 250 square feet per hour with polishing powders that contain oxalic acid or compound.
Some areas such as main entrances, registration desks, elevator lobbies, and restaurants may need to be polished every three days or perhaps even daily while low traffic areas may only need to be polished once per month. The frequency will be determined mainly by how much the floor is walked on. For example, some hotels in Las Vegas have 10,000 to 20,000 people per day walking across the floors and, from experience, we have found that polishing is needed about every three days to maintain the finish. Other hotel properties in major, non-resort, cities may only require polishing every ten to fifteen days because the rate of foot traffic is about 2,000 or 3,000 people per day. This can be used as a guideline, but the best way is to observe and test the floor being maintained. Quite simply, polish the floor and watch how long it takes before it begins to go dull in a given area then adjust the polishing frequency accordingly. Based on the labor hours available, polish the high traffic areas each day and as much of the lower traffic areas as possible.
Dust mopping and damp mopping should be done several times a day or, at the very minimum, once per day. Dust mopping should be done with a clean, non-treated dust mop as many times a day as possible. The more you dust mop the better. The floor should be damp mopped at least once a day with a good quality neutral cleaner. A looped or flat mop works best. Do not over wet the floor, a light damp mopping is all that is needed. Particular attention should be given to mopping into the grout line lengthwise. As you dust mop, much of the dirt falls into the grout line and can only be removed by mopping it out. Note, that if the grout is of the sanded type, do not use this method because it may abrade the mop and leave the lint or fibers in the grout. Sanded grout should be scrubbed periodically with a brush and the residue sucked out with a wet vac.
Make certain that the cleaner you use has a “neutral” pH of seven(7). A stone soap or cleaner/conditioner is best. High alkaline or mild acidic cleaners can etch and damage the finish. Be careful with concentrated “no-streak” cleaners. Although they may be a neutral pH, some contain chelates which can dull the finish. Chelates dissolve or destroy calcium in the water and eliminate hard water deposits. Since marble and limestone contain a large amount of calcium, the chelates also attack the finish. The best way to be sure your cleaner is neutral and will not damage the finish is to test it yourself. You do not have to be a chemist to do this, just pour a drop about the size of a quarter full strength onto the stone surface and let it stand five or ten minutes if, after you dry it off, a dull spot or “etch” is left the product should not be used. If the surface is not etched, the product is ok to use. Any spills that occur throughout the day should be cleaned up immediately with neutral cleaner or clean water. Then timely buffing with a high speed floor machine using a white polishing pad to “pop” the shine on a clean floor.
Last, but very importantantly, keep mops, rags, sponges, dust mops, and other supplies to clean the marble separate from other cleaning supplies. A mop used in a kitchen may have grease or oil in it. A mop used in a restroom may have acid from toilet bowl cleaners or urine in it. Both can have a negative affect on polished stone floors. Over time, if the high traffic areas become too worn to polish back to an acceptable finish, they should be refinished with diamond abrasives to restore the clarity and depth.