Granite is normally a coarse grained igneous rock that is comprised of quartz, feldspars and micas. The quartz will be be the lighter color minerals with the remaining consisting of feldspars and muscovite. The dark minerals are hornblende or biotite. Granite is by far the most common rock found in the outer crust of the planet. Granite is formed by the cooling of magma in the ground.
Marble is metamorphosed sedimentary carbonate rock. Limestone or dolomite (carbonate rocks) are the typical base minerals. The recrystallization of the carbonate minerals result in Marble. Often the original structure of the carbonate rocks are modified during the metamorphism to render the marble unrecognizable from its original state. The swirling and veins in marble often result from mineral impurities which are in layers in the original limestone or dolomite.
In our industry the term “Granite” is used to describe many stone slabs that are in fact not granite by a geological definition. What does this mean to you? Well not much as long as your countertop does not etch from common acids or scratch from a knife. It really is a simple test. Simply take a lemon and cut it in half, leave in the stone in question for ten minutes or so. Remove the lemon and look for etching of the surface. If the lemon had no effect, you have passed the first half of this simple test to determine if the stone is acid resistant. The next test is to take a knife and drag it across the stone. Does the stone readily scratch? If not you, are dealing with a Mercantile Granite that is suitable for the abuse that is common in a kitchen. Marbles, Limestones, Onyx, Travertines will not pass the test which is why those materials are more suitable in areas that don’t involve cooking.
Around eight years ago the granite slab manufacturing industry began to resin granite, marble, limestone and other stone slabs. The process is incredibly important as it helps seal and strengthen the stone. Resining granite is done after the slabs are cut from the granite blocks. The slabs are pressure washed to remove slurry and open any pores or natural fissures in the stone. The slabs are then dried in an oven. As the slabs leave the oven the slaps are sprayed with a penetrating resin which soaks into the slabs consolidating any fissures and filling the microscopic pores in the stone. The resin is then ground off the face of the slabs leaving the resin in the pores and fissures. The slab is left with a glass like finish that is resistant to stains. Be sure to ask for resined granite slabs when you starting looking for material. Reputable companies only purchase resined granite and marble slabs. Resined slabs are the true engineered stones of the industry.
We like to think so. Unfortunately, it is not actually classified in a way the allows it to get LEEDS points. The two biggest criteria are 1. Does the countertop use recycled material and is it a renewable resource? 2. Was it made within 500 miles from where it was installed? That’s a layman’s version of LEEDS as it relates to countertops. Let’s discuss some other factors that make granite one of the “greenest” choices available to you. First and foremost is countertop life cycle. A properly installed granite countertop will last as long as your home and never needs replacing….it will look as amazing in twenty years as it does today as long as it is maintained correctly. today as it does in twenty years. Second consideration is carbon foot print. The amount of Co2 produced in the extraction of granite is actually very low when compared with man made countertops. Couple that with a product that lasts a life time and you have one very green product. We wont run out of granite any time soon….it’s what the crust of the planet is made of.
As the name implies it is a countertop product that is made of quartz and resins. Before granite slabs were resined Engineered Stone had one major advantage over its natural counterpart, it was difficult to stain. Now with the advent of resined slabs that advantage is gone. The primary difference is the appearance. Man made products come in a large range of consistent color which do not occur naturally in nature. You often see engineered stone being used in commercial setting or contemporary ones. At the end of the day you have to decide which look is best for your countertops, price may also be a factor. Note: Engineered does not hold up to heat as well as granite.
In most cases the answer is never…..or years and years after it is installed. Sealers are solids that have been emulsified in a solvent. They are designed to penetrate the stone taking the solids with them. When the solvent evaporates (think paint) the molecules lock into the stone and seal it. Combine one good coat of a quality sealer (which we will do for you in our shop) with the resin applied by the factory you will have a very stain resistant top that will be virtually maintenance free. Rarely, if ever will you need to seal granite that has been resined and properly sealed. Over time, in the unlikely you do see some water absorb then simply reseal. We can help you with this in the unlikely event your countertops need to be resealed. Remember, companies that sell sealers would love you to seal your counters every couple weeks….think about it.