Assertion: astatine's isotope | /r/AtLocation | nature
Facets:
value: subsequently
type: TEMPORAL
Source sentences:
text: Four isotopes of astatine were subsequently found in nature, although it is the least abundant of all the naturally occurring elements, with much less than one gram being present at any given time in the Earth's crust.
text: Four isotopes of astatine were subsequently found in nature, although it is the least abundant of all the naturally occurring elements, with much less than one gram being present at any given time in the Earth's crust.