Many fabricators will try to blame cracks in stone installations on natural fissures that occur in the stone. Sometimes they are right and sometimes they are wrong. If one looks up the word "fissure" in the dictionary, guess what? A fissure is a crack. Most fabricators need to describe the natural fissures in the stone as "naturally occurring" as part of the formation of the stone. Cracks, on the other hand, should be called "breaks" caused by external forces on the stone. So if someone stands or sits on the stone, it could develop a break. Of course, the most likely place for a break to occur is on a natural fissure. So, stone must be handled and examined carefully.
This is a tricky topic and is open for debate, but you need to communicate to your customer the difference between naturally occurring fissures and those caused by external forces.
Vinegar and water
I cannot believe how many times I have heard tile installers recommend cleaning marble or limestone with vinegar and water. Vinegar is an acid and will etch calcium-based stone. Never use vinegar on any stone surface. Marble and limestone are generally the most susceptible, but there is also some granite that will be damaged by vinegar.
Saturating stone with water will remove an oil stain
I heard this one recently from a student who told me some expert offered it as a way to remove oil stains from stone. Believe me, it does not work. In theory, because oil will float on water, you would think that this makes sense. However, the oil is trapped in the pores of the stone and no amount of water is going to force it out. The best way to remove oil is with a poultice and a degreasing chemical. For instructions on poulticing, see my Web site at www.ntc-stone.com.
All stone with veins is marble
This is another fib I hear all the time. Many people believe that if a stone has veins then it must be marble. This is totally false because veins can be observed in granite and limestone as well.
The darker the stone the softer it is
Again, untrue. There are some really dark granites that are as hard or harder than some of the lighter colored granites. The same can be true for marble and limestone.
Granite harbors bacteria and emits harmful radon gas
In past articles I have dealt with both of these falsehoods. Here is a brief summary.
Rumor has it that granite countertops are unsafe, harbor bacteria and produce disease. This is absolutely FALSE. NIOSH and the CDC have no reports of granite or any other stone used in countertops being unsafe. If stone is unsafe and unsanitary why are stone cutting boards allowed on the market? Why is stone used in food laboratories? There is no known proof of any illness caused by using stone as a countertop. Of course, like any countertop, stone countertops should be cleaned regularly.
There are also rumors that granite contains harmful radon gas. This is untrue. There is so little radon in granite that one would have to live to be 10,000 years old for it to have an ill effect. There is more radon coming from the ground and the concrete that your house is built on.
As the years progress and I get grayer, I hear more falsehoods and myths. I will keep you posted on any new ones.