Assertion: berkelium | /r/HasProperty | concentrated on earth
Facets:
value: in certain areas
type: LOCATION
value: mostly
type: DEGREE
Source sentences:
text: On Earth, berkelium is mostly concentrated in certain areas, which were used for the atmospheric nuclear weapons tests between 1945 and 1980, as well as at the sites of nuclear incidents, such as Chernobyl disaster, Three Mile Island accident and 1968 Thule Air Base B-52 crash.