Assertion: chalcedony | /r/CapableOf | owe its color
Facets:
value: including titanium
type: OTHER
value: including iron
type: OTHER
value: including nickel
type: OTHER
value: including copper
type: OTHER
Source sentences:
text: Chalcedony owes its color to quartz impurities, most often including iron, nickel, copper and or titanium.