Assertion: swan's feather | /r/HasProperty | stained orange-brown
Facets:
value: often
type: TEMPORAL
value: by tannins
type: OTHER
value: by iron
type: OTHER
value: in the water
type: LOCATION
Source sentences:
text: The white feathers present on the heads and necks of adult mute swans are often stained orange-brown by iron and tannins in the water.