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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 also helps regulate cell permeability. It is also very alkaline-forming and critical for the maintenance of acid-base balance of the blood and the body tissues. Calcium is involved in the secretion of male and female hormones, cell division and the water balance of the body.It also stabilizes cell membranes, helps muscles relax, and slows nerve transmission and the heart rate. Calcium also helps prevent fluid loss from cells and from the blood.n this case, calcium becomes biounavailable. That is, an excess occurs in the tissues but it is not available to the body. It becomes essentially a toxic mineral, causing calcium deposits in the joints, arteries, kidneys, brain and elsewhere.