Bone mineral

Bone mineral is formed predominantly from carbonated hydroxyapatite[1][2] with lower crystallinity.

[1][3] Bone mineral is formed from globular and plate structures[3][4] distributed among the collagen fibrils of bone and forming yet a larger structure.

Often the plural form "bone salts" is used; it reflects the notion of various salts that, on the level of molecular metabolism, can go into the formation of the hydroxyapatite.

In fact, the bones function as a bank or storehouse in which calcium can be continually withdrawn for use or deposited for storage, as dictated by homeostasis, which maintains the concentration of calcium ions in the blood serum within a particular range despite the variability of muscle tissue metabolism.

The parathyroid and thyroid glands in the neck produce those hormones; thus, problems with those glands (such as hypo- or hyperparathyroidism or hypo- or hyperthyroidism) can create problems with bone mineral density (as well as hypo- or hypercalcaemia).