Assertion: pyrite | /r/ObjectUse | used since classical times
Facets:
value: to manufacture copperas
type: PURPOSE
Source sentences:
text: Pyrite has been used since classical times to manufacture copperas (iron(II) sulfate).
text: Pyrite has been used since classical times to manufacture copperas, that is, iron(II) sulfate.
text: Pyrite has been used since classical times to manufacture copperas, that is, iron(II) sulfate.