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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.
When trying to understand why calcium is important, itâs essential that you know exactly what role calcium plays in your body. Approximately 99% of the calcium currently in your body is stored in your teeth and bones. Calcium is also important for many other bodily functions, such as muscle contraction and exocytosis.