What is limestone?
Limestone is a kind of sedimentary stone that is very common all
over the Mediterranean and Europe.
Limestone is made out of the shells of zillions of little tiny sea
snails and creatures like that. These snails and stuff lived in the
sea, billions of years ago, and when they died they fell to
the bottom of the sea and rotted, but their shells, which were made
of calcium like your teeth, did not rot and just stayed there. Pressure
from other shells, and from the water, and from sand being washed
over the shells, squashed them all together into rock.
Many many years later, the sea changed where it was, and all this
calcium-rock (limestone) was left on the land where people could quarry
it (dig it up).
When limestone gets even more squashed, it can turn into travertine
Limestone is also the main way you get lime, which is one of the things
you make cement out of. To get lime, you
have to burn limestone in lime kilns, and then what is left is lime. In the Middle Ages, people burned most of the statues of ancient Greece and Rome to turn them into lime.
Bibliography and further reading:
Eyewitness Guides: Building, by Philip Wilkinson (2000).
A Golden Guide from St. Martin's Press, by Frank Rhodes (2001).
Karen Eva Carr, PhD.
Assoc. Professor Emerita, History
Portland State University
Professor Carr holds a B.A. with high honors from Cornell University in classics and archaeology, and her M.A. and PhD. from the University of Michigan in Classical Art and Archaeology. She has excavated in Scotland, Cyprus, Greece, Israel, and Tunisia, and she has been teaching history to university students for a very long time.
More about Professor Carr's work on the Portland State University website
Today's special find from Amazon:
This is a great kit: mold your own human skeleton, put it together, attach the magnets and stick it to your fridge! Learn what's inside your body.
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