Assertion: thorium | /r/HasAspect | several isotopes
Facets:
Source sentences:
text: Thorium has several isotopes but there are no naturally occurring fissile isotopes.
text: Thorium has no isotopes that readily fission to produce energy.
text: Thorium has a number of isotopes.
text: There is actually no single answer to this question, because Thorium has several isotopes, each with its own half-life.