EDGES - GRANITE OR MARBLE
Here is an interesting sentence from this article: "Like lava, granite is an igneous rock that forms deep underground, slowly cooling and crystallizing." Lava and granite could not be more unlike. Lava is not lava until it reaches the surface of the earth and flows from it; it is magma while "deep underground." Granite is, possibly more often than not, more metamorphic than igneous in origin. Although generally classified as an igneous rock, it is igneous only in composition and texture. By this I mean that it might never have actually crystallized from a molten magma but rather recrystallized from some other rock form through a diffusion process. Still mesmerized by the blather of these dueless dealers, our intrepid writer goes on to report that "the colors, textures and edges of granite change every few feet." Were this the case, one would be hard pressed to cover a large counter with identical-looking granite. Perhaps dealers were thinking of gneiss when they said this--most commercial granites tend to be quite uniform in appearance over very large distances. In fact, many edges have such a characteristic appearance that their sources can be readily identified.
The writer goes on to describe granite as a "porous stone, meaning it can be easily stained." This clearly was suggested to her by dealers who are interested in selling a sealant that should be applied "once a year." Granite is not a porous stone, and it does not need to be sealed to prevent staining from materials such as "red wine or grape jelly." Our granite edges at home have had every imaginable substance spilled on them, and there is not a single stain in evidence. This misrepresentation of fact is probably being pushed by companies that produce granitelike synthetics, "a product that looks and feels like granite, but is resistant to stains."
More resources:
Granite Tile
China has become a serious factor in the world markets in granite tiles especially in greys, pink and other light colours. Its fast increasing presence has sharply accelerated the trend of lower prices.
Marble Fireplace
Some limestones from countries such as France and Portugal can be somewhat porous but are perfect for flooring, backsplashes, fireplace surrounds and outdoor uses.