Uranium Ore

Actual Uranium Ore that you can buy on Amazon. On a technical level this is actually a very small amount of depleted Uranium so it is not really dangerous and emits such low amounts of radiation as not to be significantly dangerous.

There is no way you can reasonably build any weapons using it, but at the same time I would not eat it. Just be very careful how you behave with this as it is legitimately uranium so do not ship it or send it in the mail. The actual use of the product is in testing Geiger meters and the like, so it does have a legitimate scientific and educational use. Most people will probably just be surprised that you can buy Uranium on Amazon.