Limestone is a sedimentary rock found in abundance around the world; traditionally it has been more associated with architecture than limestone countertops. There are many different types of limestone, varying in color, strength and porosity.
Limestone consists mainly of calcite that was deposited by the remains of marine animals. Its main components are calcium carbonate also known as carbonate of lime. When it contains magnesium carbonate, it is then called magnesian or dolomitic limestone. Crystalline limestone is called marble. Limestone countertops varies in hardness, some are as soft as marble, whilst others are more scratch resistant like granite.
Canada is the main source of quality limestone in North America. Limestone is very popular in industrial kitchens’ as it stands up well in humid stuffy conditions. It is the perfect surface to use to make pastry, ad it keeps everything cool.
However, since one of limestones main ingredients is calcium carbonate,
it does not mix well with acidic solutions as in the long term it reacts and stains. Application of sealants is recommended to protect the porous material from stains. Once impregnated it is protected from both dirt and water.
The amount of sealer to be used depends on the porosity of the stone and it is best to ask your supplier. Two or three thin coats are more effective than one thick coat. All limestone has a saturation point and when this is reached it is incapable of absorbing any more sealer. However it is important to get as much information as you can from your supplier, as every piece of limestone rock is different.
You cannot even be certain that limestone taken from the same quarry will be consistent. It depends on the depth from which it was taken. Excessive sealing can in some cases leave a streaked look on the surface of your limestone countertops and this is difficult to remove. The sealant should not be applied until the limestone countertop has been installed and cleaned. It is best to apply to a completely dry surface.
Being a natural stone product the range of available colors for limestone countertops is dictated by what is being quarried. There are, however, some shades found in limestone that do not exist in other natural stones, such as particularly vibrant blues and greens. Different varieties of limestone are less porous; they will absorb less liquid and last longer. Granite is the hardest limestone.
How to Remove Stains from your Limestone Countertop
The porosity of limestone countertops actually makes them easy to clean. You need a poultice to sit on top of the stain and “draw it out” from the rock.
If you have not been given specific cleaning instructions from your supplier
you can use a whitening agent to make the poultice.
Hydrogen peroxide is mixed with distilled water and this is best left on the stain for twenty four hours and rinsed clean. Sometimes a second application may be necessary especially if the stain has been caused by acidic substances. To avoid excessive use of a poultice it is best to “mop up” any spillages when they occur.
Limestone is extremely heavy and a limestone countertop can weigh 200lbs or more, so it is a job best tackled with helpers. Because it is large sections it is simplicity itself to install. First the pieces are laid out for a dry fit on a level surface.
The gaps are fixed with epoxy, which you have mixed with a tint to complement the color of the limestone countertop and the hardener. This mixture sets solid fairly quickly so everything must be ready before it is made. Once the epoxy has been applied push the slabs together, using a razor blade to scrape off the excess.