Assertion: fluorine | /r/HasProperty | occurring
Facets:
value: naturally
type: MANNER
value: in the earth
type: LOCATION
Source sentences:
text: Only fluorine-19 is stable and naturally occurring; therefore, fluorine is a monoisotopic and mononuclidic element, and only artificially produced fluorine isotopes have atomic masses other than 19.
text: Fluorine is a naturally occurring element in the earth.
text: Fluorine is a naturally occurring gas that is quite irritating to the eyes, skin, and respiratory system.
text: Only fluorine-19 is stable and naturally occurring; therefore, fluorine is a monoisotopic and mononuclidic element, and only artificially produced fluorine isotopes have atomic masses other than 19.
text: Fluorine is a naturally occurring element in the earth, but elemental fluorine is too reactive to be found in nature.