7-5-8mm peach AAA loose freshwater pearl 1/2 drilled 24 matching pair 48 pc

Description: 7-1/2-8 mm AAA button loose freshwater pearl 1/2 drilled 24 matching pair 48 pieces with Free Shipping Cultured pearls are the response of the shell to a tissue implant. A tiny piece of mantle tissue (called a graft) from a donor shell is transplanted into a recipient shell, causing a pearl sac to form into which the tissue precipitates calcium carbonate. There are a number of methods for producing cultured pearls: using freshwater or seawater shells, transplanting the graft into the mantle or into the gonad, and adding a spherical bead as a nucleus. Most saltwater cultured pearls are grown with beads. Trade names of cultured pearls are Akoya (阿古屋), white or golden South sea, and black Tahitian. Most beadless cultured pearls are mantle-grown in freshwater shells in China,and are known as freshwater cultured pearls. Cultured pearls can be distinguished from natural pearls by X-Ray examination. Nucleated cultured pearls are often 'preformed' as they tend to follow the shape of the implanted shell bead nucleus. After a bead is inserted into the oyster, it secretes a few layers of nacre around the bead; the resulting cultured pearl can then be harvested in as few as twelve to eighteen months. When a cultured pearl with a bead nucleus is X-rayed, it reveals a different structure to that of a natural pearl (see diagram). A beaded cultured pearl shows a solid center with no concentric growth rings, whereas a natural pearl shows a series of concentric growth rings. A beadless cultured pearl (whether of freshwater or saltwater origin) may show growth rings, but also a complex central cavity, witness of the first precipitation of the young pearl sac

Price: 12 USD

Location: Bowling Green, Kentucky

End Time: 2024-11-30T22:06:37.000Z

Shipping Cost: 0 USD