Assertion: metal | /r/CapableOf | lead stable metal
Facets:
value: by 1900
type: TEMPORAL
Source sentences:
text: By 1900 three metals with atomic numbers less than lead (#82), the heaviest stable metal, remained to be discovered: elements 71, 72, 75.
text: By 1900 three metals with atomic numbers less than lead (#82), the heaviest stable metal, remained to be discovered: elements 71, 72, 75.