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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. Calcium is an essential bulk mineral. It makes up bones and teeth and is essential for the transmission of information along the nerves and is used in the contraction of muscles. The importance of the right calcium balance for the maintenance of health can not be overestimated.t makes up bones and teeth and is essential for the transmission of information along the nerves and is used in the contraction of muscles. The importance of the right calcium balance for the maintenance of health can not be overestimated.