About Limestone
What’s a limestone?
Fossil Oro
Limestone is a sedimentary rock composed largely of
calcium carbonate (CaCO3). It is formed by accumulation
on the ocean floor of all kinds of shells and skeletons of
marine animals over millions of years before our era, at a
time when the surface area and volume of the oceans
were much larger.
For instance, Limestone is the most common rock all
around the Mediterranean basin, in France, Spain, Italy,
Turkey, Israel, and Egypt.
Limestone is recognizable generally by the presence of fossils. It is the basis of many
materials.
What’s a marble?
Marble is a metamorphic rock resulting from regional or
at times contact metamorphism of sedimentary
carbonate rocks; limestone. This metamorphic process
causes a complete re-crystallization of the original rock
into an interlocking mosaic of calcite and dolomite
crystals. The temperatures and pressures necessary to
form marble usually destroy any fossils and sedimentary
textures present in the original rock. Geologists use the
term "marble" to refer to metamorphosed limestone.
What’s a travertine ?
Travertine is formed by calcium deposits on
the vegetation (such as moss or algae), the
emergence of certain sources or streams with
small waterfalls. Carbonate precipitates due
to water turbulence. Vegetation then pushes
on the new frame, and the process begins
again, in cycle. Travertine is a sedimentary
rock a mainland limestone.
When pure it is white in color, but most often the dominant color tends toward gray,
yellowish, reddish or brown, depending on the impurities.
This rock can indeed have small cavities called (vacuoles) that are unevenly distributed.
What’s an Igneous Rock?
The oldest type of all rocks is the igneous rock. Deep inside the earth, the temperature is
very high and the minerals there are in liquid form called magma. As the magma pushes
towards the earth's surface, it starts to cool and turns into solid igneous rock.
All igneous rocks do not cool the same way. Some cool slowly, deep under the earth's
surface. These are called intrusive igneous rocks. The slow cooling formS rocks with
large crystals. Granite is an example of a rock that cooled slowly and has large crystals.
Other rocks formed when the magma erupted
from a volcano or reached the earth's surface
through long cracks. Magma is called lava when it
reaches the earth's surface. Lava cools quickly
and forms rocks with small crystals. They are
called extrusive igneous rocks. Basalt is an
example of this type of rock.
What are the differences between these stone?
Limestone, marble and travertine have the same chemical properties but they have different
physical properties. They are all sensitive to acid unlike granite and Lava yet they vary greatly
in density and porosity.
Limestone is the only stone where you can see fossils. Marble has in general a lot of veins.
Travertine on the other hand has small cavities.