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