Granite is a tough, durable rock composed primarily of three different minerals. These minerals are easy to see due to their different colors. The white mineral grains found in granite are feldspar. The light gray, glass-like grains are quartz, and the black, flake-like grains are mica.
Starting 325 million years ago as a large, hot (1300 degrees to 1400 degrees Fahrenheit) mass of magma or molten rock. This magma originated when some of the earth's crust melted - probably at a depth of about 11-12 miles. The magma rose upward and came to rest about nine miles beneath the surface. There it cooled very slowly - taking more than a million years - and solidified into granite. That was more than 300 million years ago.
Since then, the granite has been pushed upward, and the land above it has been removed by erosion. The result is a granite deposit that lies just beneath the earth's surface where it can be easily, safely and economically quarried.
Improved stone-working technology has made granite countertops very affordable compared with manmade hard surface materials. With granite, the resale value of your property will also grow with time.
With ordinary use, granite does not stain or burn. Granite is highly stain resistant and will withstand almost any element it comes up against including heat and cold. Should you have a stain that does require attention, please reference our Stone Care Guide.
Second only to diamonds in hardness and durability, granite has a toughness that surpasses any other countertop material. It cannot be scratched, cracked or chipped in ordinary use.
Granite continues to be used and approved in food and medical applications. The CDC (Centers for Disease Control and Prevention) has no records of granite harboring bacteria, and has no reports of people becoming ill from bacteria in granite. With regular cleaning, granite is far less likely to support bacteria than butcher block or even laminated materials with top-mounted sinks. This claim has also been tested by the Hospitality Institute of Technology and Management. Their article can be found at www.hi-tm.com under "Publications and Reports."
Link to article: http://www.hi-tm.com/Documents/Countertops.html