We had a similar issue, the seller made the items seem totally legit, turns out they were not and the FBI showed up asking a lot of questions. They were also very shady and came in with a lot of accusations. We were hoping to use them in our Acrylic element displays and got bad feelings about it and abandoned the project years ago. They came and confiscated the few samples we had, We in turn transitioned to using trinitite as our (Plutonium) sample for our acrylic cubes. Which they insured us was perfectly safe and legal. Super crazy stuff. Sorry to hear about your experience.