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Calcium is dull gray, but it is shiny when scratched. Other physical properties. Calcium is an excellent conductor of electricity. It is very soft and easily scratched. Chemical properties. Calcium reacts rapidly with air to form a coating of gray oxide, and it burns with a red flame.
Calcium is the most plentiful mineral in the human body. Almost all of it â 99% â is stored in the skeleton, where it serves to maintain healthy bones and teeth.But that's not all it does. Calcium is also essential for the normal functioning of muscles, blood vessels, and nerves.Tiny amounts are dissolved in the fluid inside and outside every cell in the body. Too much or too little calcium can be deadly to those cells, so the body carefully controls its blood levels.alcium is the most plentiful mineral in the human body. Almost all of it â 99% â is stored in the skeleton, where it serves to maintain healthy bones and teeth.