(Jarrow Formulas) Jarrow Formulas provides the most complete nutritional regimen for bones and joints with this Vity Award winning calcium. Utilizes hydroxyapatite calcium (MCHA), the same form found in the human body. Includes the complementary set of vitamins and minerals for skeletal health. And includes the correct calcium-magnesium ratio. For best results use with BioSil, the biologically active silicon.