Granite Use

[Frank Hagan]

We have a dark brown with red fleck granite in our kitchen, and we seal it yearly. We sometimes cut on it, but everyone is right ... the knife dulls so quickly that it discourages you from doing that! We have never noticed any staining and while we have had the granite for only a few years, it is over 10 years old (it was a "pull up" from my SIL house that happened to fit our kitchen with minor mods).

My SIL is a designer specializing in high end renovations, and she echos the comment here about Silstone. It is the most forgiving surface she uses. But in her own kitchen she used black granite.

There is one thing that I have been warned about ... don't allow anyone to jump up and sit on the relatively narrow piece that runs in front of the sink. Its not supported well enough to take the weight, and will crack at the corners.

[Jim Becker]

Frank and Ken, I'm actually mulling over the surface options for the cabinetry for our upcoming home addition project. I like the idea of Silstone or similar...the problem I'm having is that it doesn't seem possible to get a dark grey or black in a matt finish. Everything is just too shiny for my liking! But I suspect I'll have to settle for it anyway.

[Owen Gregg]

Hi Ken,

Silestone, along with its brothers Zodiaq, Caesarstone, Cambria and a couple others I'm sure I'm forgetting will stain. It is true that by far and large engineered quartz surfaces are much more resistant to staining, but it is also true that once stained, they are much harder to repair, if they can be repaired at all. All that said, they are definately reliable and generally great, worry-free tops.

As far as heat goes, since most engineered stones have a composition of 6-8% epoxy, I would say granite can take much more heat than any of them. Again, much of this hinges on what type of granite you use, but I'm making comparisons using middle of the road material in most cases, and as far as heat absorption, granite is fantastic. I would definately tell people engineered stones are in general stronger and much less prone to staining than granite, but not that they can take more heat.

Frank,

If she used black granite, then it's most likely a very durable and heavy one that is as close to a non-porous granite as you can get. An excellent choice for a working kitchen in my humble opinion.

As far as jumping on the front of the sink, again right on all counts; I'm a firm believer that this should be common sense to most adults, though reality has proven me wrong a few times.

Jim,

Your granite shop should definately be able to hone a sample for you to vaious degrees. It's MUCH easier to bring a polish down on engineered stone than it is to bring back up, especially on the face. A good fabrication shop should definately be able to show you samples of stuff polished to 600, 800, and 1000 grit within a fairly short amount of time.

[Owen Gregg]

I do not want to hijack the thread, but I have a question regards granite. I recently came by 77 granite sink punch outs 5/4 thick. I plan to cut them into 8x14 tiles and use as countertops for new kitchen cabinets and new vanities I plan to build. My question for you smart guys: Should I lay the tiles on cement board with thin set and grout the same as ceramic tile or is there some process unique to granite? How do the professionals handle seams on countertop installs? Also, will the cement board support the weight without additional underlayment or should I use 1/2 or 3/4 ply beneath it. As I mentioned the tiles will be 1 1/4 in thick, so additional ply underlayment will drive the countertop to 2 plus inches. Thanks for any advice.
Bill

Hi Bill,

I had a longer response typed up and then it vanished somehow. To make it short, I would advise against this for a number of reasons:

The weight of your tops will be immense-I would suggest clearing it with some kind of engineer just to be sure its safe.

The time you put into this endeavour will be huge considering all things that may go awry.

The sink cutout won't be fun-neither will the cook-top if it's drop in.

It you plan on polishing anything, it will be a nightmare.

I'm thinking you need at least 3/4" ply underlay just to start, followed with 1/2" cement board, and by the time that's all said and done you may have a top nearly 3" thick!

Tile will be much faster and easier, and maybe cheaper if you put a price tag on your time at all.

What we use on job site seams will not work with what you are planning. You would have to use silicone (Gets ugly in high traffic areas) or grout (Pain in the but to clean IMHO), or something else.

I use granite cutouts all the time for table inlays, end table tops, etc. A vanity may not even be out of the question; but what I see is a long process of one headache after another that may frustrate the devil out of you.

Best of luck in whatever you decide,
Owen

[Russ Filtz]

FACTOID - Granite tends to have higher background radioactivity than most stones. This is esp. true of pink granite. The pink color comes from lead oxide and lead is a product of decomposition of some radioisotopes, meaning traces of the original material the lead came from may still be around.

Don't think it's super high or anything, kind of like getting more rays taking an airplane trip or something. Have to do some more google searches!

[John Downey]

Well, yes and no. True granite does tend to have a very slightly higher radioactivity than say, sandstone, but its nothing to worry about. The pink granites I think you may be refering to have a large quantity of a potassium feldspar mineral that has a fleshy pink color and is also responsible for the slight radioactivity, containing trace amounts of a radioactive potassium isotope and its daughter elements, as well as accessory minerals like zircon and garnet, which also contain trace radioactive elements. The increased exposure due to installation of almost any stone countertop (with the exception of of big uraninite viens running through it) is so slight as to be laughable.

Unfortunately, the countertop industry seems to classify stone products in a very general way, either marble (including travertines), slate, soapstone, and everything else is called granite. In general, true granites will not stain, as they are very impermiable, and have a heat capacity in excess of any other material available, unless you want to go with a similar thickness of stainless steel or copper. The silicate minerals in granite are not especially suseptable to acids, at least not in household kitchen concentrations. While not quite bullet proof in a literal sense, most of the salesman's warnings regarding the fragility of natural stone comes from marbles and soapstones, which are indeed somewhat delicate. Some of the many other stones labeled as "granite" may be more delicate than the true silicious igneous stones, but not in a class with marble.

[Jim Becker]

John, I've never seen marble, slate, soapstone, etc., refered to as "granite" in this area. They are sold as what they are. While I used a specialist in soapstone for my counters in the end, I visited a LOT of local stone establishments and all of them had the materials classified for what they were as far as we could tell.

[John Downey]

Sorry I wasn't more clear, I meant to point out that if its not sold as marble, slate, or soapstone, then it is labeled granite irregardless of whether it is actually a granite or not. I suppose it doesn't really matter, as those stones lumped as granite tend to have similar properties, though some of the metamorphic rocks could be a bit more sensitive to acids than granites are. Never meant to imply anyone would sell soapstone as granite, or marble as granite. Obviously, many in the industry, like Owen, are very knowledgible about the products they work with, and though I might quibble about names, I feel their advice is as sound as can be.

[Jim Becker]

Thanks for the clarification, John. Now I understand what you are getting at and yes, being quite anal, it would bother me that non-granite was being sold as granite. Maybe this is a "kleenex" moment or something...

[Homer Faucett]

Owen's advice is consistent with all the advice I received from installers when I was in the planning stages for my new countertops. I went with 12" Labrador Green granite tiles ($6.50/sqft is a lot better than $70/sqft on my budget). I was told that 2 layers of 3/4" CDX with 1/2" cement backer board (set on the ply with thinset) is what is required.

I will be using mortar for granite and stone on top of that, and epoxy grout tinted to a color close to the stone to make the grout lines less obvious. I bought a used Dewalt commercial polisher and diamond pads up to 3000 grit to polish the edges of the tile that will show. I'll let you know how it comes out! Good luck.

[Bill White]

I tell ALL my customers to use hot pads, cutting boards, stone sealer. Then I hand them a discliamer to sign acknowledging that they understand that there is NO guarantee on natural stone products. We sell a lot of QUARTZ products too.
Bill