Tuesday, October 8, 2013

The original lime

Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust. Calcium is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.



Calcium is essential for living organisms...[a]s a major material used in mineralization of bone, teeth and shells, calcium is the most abundant metal by mass in many animals...
[C]alcium is reactive and soft for a metal (though harder than lead, it can be cut with a knife with difficulty). It is a silvery metallic element that must be extracted by electrolysis from a fused salt like calcium chloride...



It is apparent that many animals can taste, or develop a taste, for calcium, and use this sense to detect the mineral in salt licks or other sources...



Calcium is the fifth-most-abundant element by mass in the human body, where it is a common cellular ionic messenger with many functions, and serves also as a structural element in bone....







Visible spectra of many stars, including the Sun, exhibit strong absorption lines of singly ionized calcium.

Source.