PEARL

Reflection, refraction, and diffraction of light from the transparent layers give pearls their distinctive brilliance. The pearl will have a greater sheen if its layers are thinner and more frequent. The overlapping of successive layers, which scatters light falling on the surface, gives pearls their iridescent appearance. The color of pearls can also be altered to be yellow, green, blue, brown, pink, purple, or black. The most expensive pearls have a metallic sheen that is very reflective. Since calcium carbonate is the main component of pearls, vinegar may be used to dissolve them. Since the crystals of calcium carbonate react with the acetic acid in the vinegar to produce calcium acetate and carbon dioxide, calcium carbonate is sensitive to even a mild acid solution.

When an annoying small item becomes stuck between a shelled mollusk's mantle folds, natural processes can cause it to develop some type of "pearl," however the vast majority of these "pearls" are not prized as gemstones. The most well-known and economically significant pearls are nacreous pearls, which are predominantly generated by two species of molluscan bivalves or clams. A nacreous pearl is formed from layers of nacre, by the same biological mechanism as is employed in the secretion of the mother of pearl which lines the shell.

Natural pearls that have grown without human interference are extremely uncommon. For many years, this was the only way to harvest pearls, which is why they formerly commanded such high prices. To discover even one wild pearl, hundreds of pearl oysters or mussels must be collected, opened, and afterwards murdered. At pearl farms, both natural and artificial procedures are used to create cultured pearls.

Although though freshwater and saltwater pearls can have a similar appearance, their origins are distinct. Many species of the Unionidae family of freshwater mussels, which are found in lakes, rivers, ponds, and other freshwater bodies, produce freshwater pearls. Both colder, more temperate regions like Scotland and hotter climes have these freshwater pearl mussels. Chinese pearls are the majority of freshwater farmed pearls marketed today. Among the family Pteriidae of pearl oysters, which are marine organisms, saltwater pearls develop. Typically, sheltered lagoons or volcanic atolls are used for the cultivation of saltwater pearl oysters.

• Abalone Pearl: A pearl that may be discovered in the haliotis mollusc. These Pearls are often horn-shaped and frequently have an iridescent bluish tint.

• Akoya Pearl: Bead-nucleated Cultured Pearl made from Akoya Oysters, predominantly from Japan and China, but also from Vietnam, South Korea, and Australia.

• Black Pearl: Any pearl with a dark hue is referred to as a black pearl. Tahitian Pearls and black pearls are frequently used interchangeably. Frequently, black pearls are colored.

• Cortez Pearl : It is a dark pearl that is grown in Mexico's Gulf of California in pinctada maxima and pteria sterna mollusks.

• Keshi pearl: When an oyster rejects a nucleus that has been implanted before the culturing process is complete, a Keshi pearl is created. Keshi pearls are technically not real pearls since they are made entirely of nacre.

• Mabe Pearl: Rounded pearl that develops outside of the oyster's tissue and is linked to the interior of the shell.

• Melo Pearl: A rare variety of pearl from Southeast Asia that is made from the melo melo marine snail. Melo Pearls are sometimes mistaken for Pearls despite not officially being Pearls because they didn't develop within a mollusc, despite their creation in an organic marine environment and resemblance to Pearls.

• Scallop pearl: Every Pectinidae member may generate scallop pearls, which are a kind of pearl. Scallop pearls are frequently mistaken for Pearls despite not technically being Pearls because they didn't develop within a mollusc, despite their creation in an organic sea environment and likeness to Pearls.

• South Sea Pearl: A pearl made by the mollusc Pinctada maxima. Throughout the Indian and Pacific Seas, particularly in Australia, the Philippines, Indonesia, and Burma, South Sea pearls are prized and farmed.

• Tahitian Pearl: This highly prized variety of pearl is made in the black-lipped oyster and is grown close to Tahiti and other French Polynesian islands in the South Pacific.