Assertion: pyrite | /r/ObjectUse | used as a source of sulfur
Facets:
value: historically
type: TEMPORAL
value: for the production of sulfuric acid
type: PURPOSE
value: commercially
type: MANNER
Source sentences:
text: Historically, pyrite was used commercially as a source of sulfur, particularly for the production of sulfuric acid, but today sulfur is largely collected as a by-product of petroleum processing.