Assertion: mollusk's shell | /r/HasProperty | lined with nacre
Facets:
Source sentences:
text: Most molluscs with shells can produce pearls, but only the pearls of bivalves and some gastropods, whose shells are lined with nacre, are valuable.(pp300–343, 367–403)
text: Most molluscs with shells can produce pearls, but only the pearls of bivalves and some gastropods, whose shells are lined with nacre, are valuable.