Limestone can vary considerably in appearance depending on the amount of calcite present in the stone, the degree of pollution and the distribution of fossils. High calcite limestone has a very light color, while iron oxide impurities that gives it a yellow or brown appearance and the presence of coal will darken to black or gray . Limestone has a hardness rating of 3 – 4.
Repair and Restoration
The limestone can be difficult to maintain a proper maintenance unless a floor care cycle introduced by a floor treatment. Since it is usually not polished , the problem with scratches are not a big issue as it is with marble, but unless a suitable carpet solution exists, then a honed surface will lose its attractiveness. The most important factor to consider in the maintenance of limestone is the possibility of discoloration. Its calcite composition makes it susceptible to acid attack from spilled food and drink. Its high porosity can also mean oil will permeate the surface and leave stains if not properly sealed with a penetrating seal.
Daily maintenance will consist of dry and damp mopping, this should be done with a good stone soap and sometimes with just water. It is important that soap rests do not build up on the surface of the stone. Acid -based chemicals used for domestic purposes can damage the surface of marble and other calcite stones on contact. Similar damage may occur from acidic foods and drinks.
Professional regular maintenance will be required to maintain its honed and polished look. Our view is that limestone looks best with a honed or low/medium gloss, however, insist many a high gloss finish. Some low values of calcite limestone can be very difficult to polish and will therefore crystallization required.
When regular maintenance is no longer adequate, a restoration will be necessary. Problems that deep coloring and improper maintenance causes yellowing, requiring restoration. It is common to see the limestone that is very yellow and dark eddies due to poor maintenance. The use of low quality polish which contains high amounts of wax result in a stone becomes yellow with time. To crystallize or polish at this point will just fill in the dirt, resulting in a smooth but dirty yellow surface. Some of our customers are sometimes surprised to see how bright the original limestone is, when the top layer of discolored and over crystallized limestone is removed. Using diamond grinding can its true
beauty emerge again, often showing more fossils and more varied range of color.