Transient precursor strategy in mineral formation of bone.

The strategy in biomineralization of initially depositing a less ordered mineral and then transforming it into a more crystalline mature phase is probably widespread among invertebrates. The report in this issue by N.J. Crane, V. Popescu, M.D. Morris, P. Steenhuis, M.A. Ignelzi, Raman spectroscopic evidence for octacalcium phosphate and other mineral species deposited during intramembraneous mineralization. Bone (In press), using micro-Raman spectroscopy to study early mineral deposits in mice calvaria, provides strong evidence that the transient precursor strategy also occurs in vertebrates.