Are fossil dino teeth actual teeth?

[PetrosTrilobite]

Hi, i read in a website that "The best thing about fossil teeth is that they consist of the actual bone and have not been replaced by minerals from the ground."

 

How true it is?

Edited January 17 by PetrosTrilobite

[JBkansas]

Seems like a bit of both (original minerals and secondary minerals) though that appears to be true of bone as well (not specific for teeth, diagram is from an article on bone):

 

 

https://anthropology.ucsd.edu/_files/Faculty Files/schoeninger-publications/Kohn etal. 1999.pdf

Edited January 17 by JBkansas

[Opabinia Blues]

Eh, generally partially true and partially false, though this is true of bones as well. Permineralization involves mineral replacement, and this is true in both fossil bones and of course dinosaur teeth. Fossil dinosaur teeth are absolutely not chemically identical to how they were when the animal was alive. However, there is some original material present. The same is also true of permineralized bones, though I would not be surprised if a greater amount of original material survives in teeth rather than in bones due to compositional differences.

[Ludwigia]

The same principal also applies to fossilized shells. Many shells were originally made up of aragonite, which was then mostly rather quickly converted to the more stable calcium carbonate calcite.

[JimB88]

Preservation depends on many factors. It's an over-generalization to say all fossils are preserved the same way. The teeth may be permineralized at one location but not at another.

[FranzBernhard]

7 hours ago, Ludwigia said:

The same principal also applies to fossilized shells.

Calcite shells can sometimes also have "parts"* of their original composition retained. For example, Sr-isotope composition in rudist shells.

*Minus the organic content but plus some trace elements, for example Fe and Mn in many cases.

 

Here is a revived thread about this topic:

Fossils Aren't Real Bones/teeth? - Questions & Answers - The Fossil Forum

 

Franz Bernhard

Edited January 22 by FranzBernhard