Assertion: tellurium | /r/AtLocation | the ores sylvanite
Facets:
value: most often
type: DEGREE
Source sentences:
text: Tellurium is found free in nature, but is most often found in the ores sylvanite (AgAuTe 4 ), calaverite (AuTe 2 ) and krennerite (AuTe 2 ).