Assertion: opal's mother | /r/SimilarTo | pearls in chemical composition
Facets:
value: in chemical composition
type: OTHER
Source sentences:
text: Mother-of-Pearl is similar to pearls in chemical composition, but unlike a pearl, which is the result of nacre secretions emitted to protect the mollusk from a foreign irritant entering the shell, mother-of-pearl comes from the actual shell of the animal.