Assertion: protactinium's isotope | /r/CapableOf | occur as primordial nuclides
Facets:
value: naturally
type: MANNER
Source sentences:
text: Only two isotopes occur naturally as primordial nuclides: indium-113, the only stable isotope, and indium-115, which has a half-life of 4.41×1014 years, four orders of magnitude greater than the age of the universe and nearly 30,000 times greater than that of natural thorium.