The optimized conditions for phosphorus recovery as hydroxyapatite from wastewater by synthetic tobermorite through seeded crystallization were studied in this paper.
These minerals form calcium phosphate, which crystallize on the cartilage framework, ultimately forming a bone matrix that's about one-third mineral, two-thirds protein.
Sometimes, instead of oxalate, the calcium binds a negatively charged phosphate group to form calcium phosphate stones, which are dirty white in color and alsop radiopaque on an Xray.
Luckily, their teeth were made of calcium phosphate materials, which do fossilize, so we have plenty of huge teeth to get an idea of megalodon's monstrous size.
From your time in the womb until you're about 25, your osteoblasts keep laying down more collagen and more calcium phosphate, until your bones are fully grown and completely hardened.
When they get there, they secrete both a collagen-digesting enzyme, and an acidic hydrogen-ion mixture that dissolves the calcium phosphate, releasing its components back into the blood. This tear-down process is called resorption.
Teeth manage both by having two layers: a hard external cap of enamel, made up almost entirely of a calcium phosphate, and beneath it, a tougher layer of dentin, partly formed from organic fibers that make it flexible.