Because seawater beads are different from freshwater beads, seawater beads have a long cultivation time and high cost, while freshwater beads are lower. A seawater pearl oyster can only produce 1-2, while freshwater pearl oyster can produce 5 to dozens. Rare things are expensive. And the survival rate of marine shellfish is lower than that of freshwater mussels.

Most seawater pearls are round with bright luster and good health care effect. However, freshwater beads are mostly irregular in shape, with weaker luster than seawater beads, easy to maintain and strong decorative effect.

Extended data:

Pearl has anti-inflammatory, heat-clearing and sedative effects. Pearl has recorded its medicinal value in ancient medical books. Pearl contains calcium carbonate, calcium oxide, calcium phosphate, calcium sulfate, magnesium, manganese, copper, iodine, phosphorus, strontium, lead, sodium, potassium and other trace elements and amino acids, while the pearl necklace is close to the neck, and some components of the pearl can be absorbed by the skin when rubbed, which can play the role of anti-inflammation, healing and granulation.

Wearing pearl necklace for a long time can relieve the cough of pharyngitis patients, or even stop coughing completely. People who often match are not prone to pharyngitis. Patients with hyperthyroidism wear pearl necklaces, which can inhibit the growth of tumors and make them disappear slowly.

References:

Baidu Encyclopedia-Pearl