If you mean the crown and core/post are all one piece????????  Cannot tell
that without talking to the person who put in place, or getting it out and
looking at it.

If you mean a one piece post/core under a separate crown,,,,,,,,,,,,
assuming metal in the crown, , , , , no way to tell this from the above
scenario without asking the first dentist or taking it apart.

After doing dentistry for over 20 years, the only way I will attempt to
remove a crown is by slicing through the crown and pealing it off the tooth.