Removing Stains From Limestone - 2013:
Recently I was called to a home with a beautiful limestone floor in the kitchen, entry, hallway, bathroom, and office. This limestone floor was two years old and the owner had done an excellent job of maintaining the floor. One day the homeowner left a bag of garbage on the floor and the bag leaked on to the limestone floor in the kitchen. Because the floor had never been sealed the contents from the bag soaked into the limestone and created a stain. Because limestone, like travertine, is porous it will absorb liquids of all kinds. I reminded the homeowner that because many of the foods we eat are acidic (ie: tomatoes, coffee, tea, milk, eggs, vinegar, lemon, orange, pineapple, etc.) that it was a matter of time before something acidic would end up on the floor. Hence the reason why the floor should be sealed.
After conducting two separate tests it was determined that the stain had soaked down far enough that cleaning alone would not solve his problem. In cases like these we like to use a poultice. A poultice is a mixture of clay and chemicals that will help draw the stain to the surface making for a safe removal from the floor. This process usually requires (3) days for the poultice to do its thing but it is usually quite effective. After three days we go back and remove the dried out clay and then clean & polish with a hog's hair brush. This technique will work more times then not. If necessary we can place our stone grinder on the floor and remove a micro layer of stone and removing the stain at the same time.
I attempted to walk the client through the process of what he needed to do and approximately how much he would need to spend on chemicals, poultice, etc. and he decided to hire me because he wanted it done right the first time. He did not want to take a chance on making a potential bigger mistake and it costing more. Smart Thinking.