Bone mineral
Bone mineral is the inorganic component of bone. Bone mineral is formed from carbonated hydroxyapatite  with lower crystallinity.

Bone mineral is formed from globular and plate structures distributed among the collagen
Collagen is a group of naturally occurring proteins found in animals, especially in the flesh and connective tissues of mammals. It is the main component of connective tissue, and is the most abundant protein in mammals, making up about 25% to 35% of the whole-body protein content...

fibrils of bone and forming yet a larger structure.
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