Assertion: uranium | /r/MadeOf | a mixture of uranium-238
Facets:
value: naturally
type: MANNER
Source sentences:
text: It is now known that uranium, radioactive in all its isotopes, consists naturally of a mixture of uranium-238 (99.27 percent, 4,510,000,000-year half-life), uranium-235 (0.72 percent, 713,000,000-year half-life), and uranium-234 (0.006 percent, 247,000-year half-life).