Assertion: ivory | /r/ObjectUse | used in piano keys
Facets:
value: traditionally
type: OTHER
value: historically
type: TEMPORAL
Source sentences:
text: Historically used in billiard balls, piano keys and even hip replacements, ivory continues to be valued today for jewelry and other luxury objects.
text: Ivory has traditionally been used for jewelry, billiard balls, pool cues, dominoes, fans, piano keys and carved trinkets.