Assertion: oyster's pearl | /r/HasProperty | obtained
Facets:
value: from pearl oysters
type: OTHER
value: from cultured shells
type: OTHER
Source sentences:
text: Most pearls are now obtained from cultured shells where an irritant substance has been purposefully introduced to induce the formation of a pearl.
text: Many hundreds of pearl oysters or mussels must be gathered and opened, and thus killed, to find even one wild pearl; for many centuries, this was the only way pearls were obtained, and why pearls fetched such extraordinary prices in the past.
text: Both these pearls can be obtained from pearl oysters.