Assertion: tungsten | /r/HasProperty | discovered by brother
Facets:
value: in 1783
type: TEMPORAL
value: in samples of the mineral wolframite
type: LOCATION
Source sentences:
text: Tungsten was discovered by Juan José and Fausto Elhuyar, Spanish chemists and brothers, in 1783 in samples of the mineral wolframite ((Fe, Mn)WO 4 ).