The name "granite" is used to cover a group of related stones
which originate deep in the earth's molten mantle. As this extremely hot
liquid material rises and cools, it forms a crystaline, granular
structure; hence the name "granite". Granite and other
granite-like stones are formed of hard minerals such as quartz, feldspar
and mica, which are fused together into a very hard stone, which is
ideal for kitchen counters. It's polish is resistant to household acids
such as citrus and vinegar, and it is hard enough to resist scratches
from knives, pots and pans.
True geological marble is limestone that has been subjected to great
pressure and heat, which has changed its structure to a crystalline,
sugary texture. It is generally white or off-white, sometimes
translucent, with some veining or color provided by other minerals
present at its formation. Commercially, the term "marble"
applies to any compact limestone that will take a polish, which includes
most of the colored marbles, except for some of the green-colored types.
Limestone is a sedimentary rock consisting mostly of organic materials
such as skeletons and shells of marine creatures and sediments. It is
formed by material which settles to the bottom of bodies of water. Over
millions of years it solidifies (lithifies) into solid rock.
Travertine is a limestone formed by geysers like Old Faithful. When the
geyser erupts, it carries a mixture of extremely hot water and limestone
particles out through the opening in the surface of the earth. When the
water falls to the ground and evaporates, it leaves behind the dissolved
limestone, which re-hardens into stone. The new stone is full of air
pockets from gas bubbles, which gives Travertine it's characteristic
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