Assertion: gypsum | /r/HasProperty | quarried
Facets:
value: from several pits
type: LOCATION
Source sentences:
text: To make it, gypsum is quarried, crushed and then ground into powder and heated until it undergoes a process called calcining, which happens when 75 percent of its chemically combined water is driven out.
text: This gypsum was quarried from several pits before the deeper bed was mined.
text: As far west of Gypsum Creek as Salina, where gypsum has been quarried, there are indications in the subsurface of gypsum below the Wellington (and below the thin covering of Dakota formation in some areas), but it is not possible to trace individual beds throughout the area.