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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 a chemical element which is essential for living organisms, including humans. Calcium's chemical symbol is Ca. It is found in many foods. We need to consume a certain amount of calcium to build and maintain strong bones and healthy communication between the brain and various parts of the body.The National Health Service (NHS) 1, UK, says there is more calcium in the human body than any other mineral.e need to consume a certain amount of calcium to build and maintain strong bones and healthy communication between the brain and various parts of the body. The National Health Service (NHS) 1, UK, says there is more calcium in the human body than any other mineral.