The mineral constituents of bone

A KNOWLEDGE ofthe composition ofthe mineral constituents of bone is important for two reasons. First, the most popular view of the mechanism of ossification supposes that in bone formation a salt is precipitated from its saturated solution. The desirability of knowing exactly what salt is thus deposited has been con- sidered by Shear and Kramer [1928, 1] and Secondly, work on calcium metabolism frequently suggests that calcium is being laid down in, or removed from, bone [e.g. Greenwald, 1926; If, however, bone salt were first deposited in some specific form which slowly changed to the salt of adult bone, or if some labile form of calcium were removed first, such changes might be detected.