sorry to have to disappoint you but this strand of Pearls are not Natural Pearls; there is no need of going to the trouble and getting them x-rayed. Natural Pearls are NON-nucleated pearls and, therefore, they do not have a foreign bead nucleus like cultured pearls. Being completely NATURAL each pearl will never be physically identical to the pearl next to it, and you can see this with normal vision.
Firstly, your pearls are all perfectly spherical so I would be leaning towards cultured pearls or imitations. There are tests you can do at home to determine this. Add the term "tooth test" in the Google search box on the Homepage.
