Reference Terms
from Wikipedia, the free encyclopedia


Calcium is a chemical element in the periodic table that has the symbol Ca and atomic number 20.

Calcium is a soft grey alkaline earth metal that is used as a reducing agent in the extraction of thorium, zirconium and uranium.

Calcium is also the fifth most abundant element in the earth's crust.

It is essential for living organisms, particularly in cell physiology, and is the most common metal in many animals.

Note:   The above text is excerpted from the Wikipedia article "Calcium", which has been released under the GNU Free Documentation License.
Related Stories

Health & Medicine News
May 24, 2017

Latest Headlines
updated 12:56 pm ET