why do fossillised bones weigh more than normal bones?

Answer 1

Most fossil bones such as dinosaur bones, are actually no longer bone at all. The original organic material disappeared and the inorganic mineral part has been replaced by other minerals such as quartz or calcite. This happens on a molecule-by-molecule basis called "permineralisation", which is why the detailed microscopic structure is often preserved.

The voids which in life contain blood, marrow and collagen also fill with minerals. So the fossil "bone" is actually rock, hence much heavier.

More recent and rare preservation such as occurs in the the tar pits of Rancho La Brea in Los Angeles retains the original bone as the tar prevents bacterial attack on it. With the collagen gone, if the tar was removed such bones are actually lighter than living bone.

Answer 2

I thought it was because they contain more carbon when they become fossillised which makes them more dense. They can tell how old a bone is by how much carbon it contains so i'd of thought this to be the reason.

Answer 3

No, they tell the age by how much C14 is in it. C14 is radioactive and it decays into nitrogen over time. The older a bone is, the less C14 it contains. Good guess though.

Answer 4

Because the sediment that replaces the bone tissue is much more dense.

Answer 5

well i dont know of anyone who's weighed a modern tyrannosaurus bone so i couldnt compare them

Answer 6

fossilised bones are not calcium. the calcium in fossils is replaced with minerals that are much heavier than calcium.

Answer 7

Because they're heavier

Answer 8

cause there in rocks