Re: fossils stick to tongue?

["David Marjanovic" <david.marjanovic@gmx.at>]

> I have read that calcium is the mineral in question.  Apparently if the
> bone is young enough to have some calcium in it, it will stick to your
> tongue.  An old bone (more than 50,00 years or so) with all the calcium
> gone will not stick.

Phew! No, no, it's no mineral, the porosity is what makes bone stick.

Calcium is not a mineral; but many minerals are calcium salts (calcium
alone, which doesn't occur in nature, is a highly reactive metal). And bone
is calcium phosphate; the calcium usually isn't replaced, except in, say,
opalized fossils.