Assertion: cosmic ray's source | /r/MadeOf | thorium dioxide
Facets:
value: often
type: TEMPORAL
Source sentences:
text: Common sources of radioactivity: smoke detectors (Americium-241), propane gas lamps (the fabric gas mantles often contain thorium dioxide), orange Fiestaware (uranium), old glow in the dark clocks/watches/instrument dials (radium), antique 19th century yellow/green vaseline or canary glass, some rocks/stone counter tops, etc.
text: Common sources of radioactivity: smoke detectors (Americium-241), propane gas lamps (the fabric gas mantles often contain thorium dioxide), orange Fiestaware (uranium), old glow in the dark clocks/watches/instrument dials (radium), antique 19th century yellow/green vaseline or canary glass, some rocks/stone counter tops, etc.