WhatIzIt ???

[Man From Ironbark]

Bones are made mostly of collagen, bone is living, growing tissue. Collagen is a protein that provides a soft framework, and calcium phosphate is a mineral that adds strength and hardens the framework. This combination of collagen and calcium makes bone strong and flexible enough to withstand stress. More than 99 percent of the body's calcium is contained in the bones and teeth. The remaining 1 percent is found in the blood.

So not technically a bone but many may call it thus.

There are associated clues in many answers above.
Listed they are:
sand
salt
calcium, though no one has mentioned carbon
bone? not specifically.

Edited to add. I'm afraid that unless you are well travelled, these are absent from Americas.