Assertion: polonium | /r/HasProperty | isolated as element
Facets:
value: in 1898
type: TEMPORAL
value: by marie curie
type: LOCATION
value: by pierre
type: OTHER
Source sentences:
text: Polonium was first isolated as an element in 1898 by Pierre and Marie Curie, who ground down massive amounts of pitchblende in a cast iron vat.