Question

Name the most hardest substance present in a human body, which is made up of calcium salts.

Answer 1

bone is the hardest substance present in body of human , that have calcium salts
it is a connective tissue
and a fact, that The bone is 16 times stronger than the steel bar of the same size

hope this helps

Answer 2

Hardest substance in human body is enamel.
Enamel is the outermost covering of each tooth.