Cal Apatite Bone Builder provides excellent bone health support with microcrystalline hydroxyapatite concentrate (MCHC), a highly absorbable crystalline compound that provides everything found in healthy bones and is backed by more than 30 years of research. MCHC contains naturally occurring calcium, phosphorus, and trace amounts of other minerals, bone growth factors, collagen, and other vital bone proteins. This well-rounded formula is designed to support bone mineral density.