Assertion: opal | /r/HasProperty | rubbed with olive oil
Facets:
value: to prevent cracking
type: PURPOSE
value: glycerin occasionally
type: OTHER
Source sentences:
text: Opals need to be rubbed with oil (baby oil or olive oil) or glycerin occasionally to prevent cracking.
text: Opals need to be rubbed with baby oil, olive oil or glycerin to prevent cracking.