The sample was supposedly to convince Russia that HEU had been stolen from supplies under Soviet control. Uranium has an isotope signature that identifies its geographic source.
We only know the specifics of this particular transfer because of wikileaks. This might be a typical transfer of samples.
The stink of the uranium one deal and the roles of Sessions, Comey, Mueller, Podesta end others all remain hidden and protected. There were millions of dollar floating around and it is impossible to believe some of them did not land in US pockets. Bill Clinton got $500,000 just for speech to a Russian audience. Boggles the mind.
The Russian government and the Russian mob are often one and the same. One would be naive at best to trust the word of any of these players.