Nuclear material refers to the metals uranium, plutonium, and thorium, in any form, according to the IAEA.
Uranium ore concentrates are considered to be a "source material", although these are not subject to safeguards under the Nuclear Non-Proliferation Treaty.
[2] Special nuclear materials have plutonium, uranium-233 or uranium with U233 or U235 that has a content found more than in nature.
Radium is also a regulated nuclear material that is found in nature and produced by the radioactive decay of uranium.
[7] The EM also works with the National Nuclear Security Administration (NNSA) to dispose the surplus, non-pit, weapons-usable plutonium-239.