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I've always been impressed with natural stone countertops in a kitchen. Marble, granite, and soapstone are all popular, but which is the best all around and why? Are any of these affected by acidic foods or household cleaners? Which would GeoMan choose for his dream house?

Great question, and one near and dear 'cuz I am in the finishing stages of my "dream house." Yep - you need to take some time to consider how the materials will react to the wear and tear of life in a kitchen! There is an Ask GeoMan question concerning the 3 basic types of rock. It might be a good idea to revue this before we start.

There are two issues here (over and beyond the aesthetics of a particular rock): hardness, and durability in the face of chemical attack. Let's start with hardness. The countertop obviously needs to he harder than a knife, and also be strong enough to withstand incidental chipping due to bumps and so forth. In most cases, igneous and metamorphic rocks will be both harder and more durable than any of the sedimentary rocks, and all of your indicated choices are either igneous or metamorphic. But we also need to take into account the composition of the material (what it's made of). Granite is composed of silicate minerals (mostly silica and oxygen, and therefore pretty tough stuff), while marble in made of calcium carbonate (much softer than a knife), and soapstone is essentially talc (the softest mineral of all - even your fingernail will leave scratches!). Clearly, granite passes the hardness and incidental bump tests!

The other issue is chemical resistance. Since we can rule out soapstone completely due to its softness, we need to look at granite vs. marble. Marble is made of calcium carbonate (the same stuff that limestone caves are made of), and will even dissolve in water after a relatively short span of time. No matter what, the finish will dull, as will your satisfaction, if you use any calcium carbonate based material as a countertop. Once again, granite, being composed of silicate minerals, is the material of choice, and WITHOUT A DOUBT the one I would pick.

Good luck with your house, and think good things about the earth while enjoying your new kitchen.


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