Assertion: californium | /r/HasProperty | actinide
Facets:
Source sentences:
text: It is an actinide: one of 15 radioactive, metallic elements found at the bottom of the periodic table.
text: Californium is an actinide and a radioactive metal which was discovered about 70 years ago by a group of scientists in one of the universities of California, so it has got its name after the state.