A calcium blood test measures the amount of calcium in your blood. calcium is one of the

most important minerals in your body. You need calcium for healthy bones and teeth.

Calcium is also essential for proper functioning of your nerves, muscles, and heart. About

99% of your body's calcium is stored in your bones. The remaining 1% circulates in the

blood. If there is too much or too little calcium in the blood, it may be a sign of bone disease,

thyroid disease, kidney disease, or other medical conditions.Normal values range from 8.5 to

10.2 mg/dL (2.13 to 2.55 millimol/L).