Assertion: oyster's pearl | /r/HasProperty | formed
Facets:
Source sentences:
text: Pearls are formed when a foreign particle such as sand, dirt or a piece of shell enter the mollusk’s body.
text: Pearls are formed when an irritant, such as a bit of food, a grain of sand, or even a piece of the mollusk's mantle becomes trapped in the mollusk.
text: These substances are secreted in layers and a pearl is formed.
text: Pearls are formed when an irritant, such as a bit of food, a grain of sand, bacteria, or even a piece of the mollusk's mantle becomes trapped in the mollusk.
text: Over time, more and more layers of nacre are added, until a pearl is formed!
text: And when this mantle is displaced, be it naturally or artificially, into another part of its body, pearls are formed.
text: Black pearls are formed when that piece of sand gets stuck in the body of a very specific type of oyster, the Tahitian black-lipped Pinctada margaritifera.
text: To form cultured pearls in freshwater, only cutting a slit in the mantle is required; nacre is secreted and a pearl is formed.