I had mentioned testing of the sample that I posted to my GP when I showed him the sample and he said, "I don't know who I would be able to send it to". It was no big deal for me, I just want to get them out of me and I know that whatever it was could not be formed in 10 hours. If you believe this is the case why are some not able to form these "gallstones" after a number of flushes?
Good luck!