Assertion: lead | /r/HasProperty | element
Facets:
value: with the heaviest stable isotope
type: OTHER
Source sentences:
text: Lead is an element and, therefore, it does not break down.
text: Lead is the element with the heaviest stable isotope, 208Pb.
text: Lead is one of the elements which has an alchemical symbol, shown below (alchemy is an ancient pursuit concerned with, for instance, the transformation of other metals into gold).
text: Lead is one of several elements that can be found naturally in its pure form.
text: Lead is one of the few elements which can be found in nature in pure form.
text: Lead is an element that occurs naturally in the earth.
text: Since lead is an element, it does not have a chemical formula; however, its chemical symbol is Pb.