Assertion: calcium oxide | /r/HasProperty | obtained
Facets:
value: from limestone
type: OTHER
value: by roasting limestone
type: MANNER
value: usually
type: DEGREE
Source sentences:
text: In industrial glass: Chemical compounds Lime is obtained from limestone (calcium carbonate) or from dolomite (calcium magnesium carbonate) when magnesium oxide is also needed.
text: Quicklime is usually obtained by roasting limestone in a furnace at about 1000 °C.
text: Lime is obtained from limestone