Pearl Culture

Pearls, since time immemorial have exercised a strange fascination over man.   It is the only gem that comes into existence by the workings of a living being and does not require any mining, polishing or external efforts to enhance its beauty.  A pearl in its entity is iridescent, glowing, with a luster that no other gem can match. 

It has been coveted by the ancient civilizations, adorned their women, launched their military campaigns, served as currency, immeasurably increased a person’s wealth and prestige, hoarded and bartered.  As time continued its march, the people and their powers declined, but not the hold pearls have over men, new civilizations coveted the pearls as much as their ancestors did.  They ruthlessly foraged the ocean and sea beds for pearls, till the end of the 19th century when the ancient pearl trade ended due to over harvesting, and pollution.

When natural pearls could not be found, and the desire for pearls remained, man helped nature along, to once again produce pearls.  Pearls so formed due to human intervention are called as cultured pearls and the entire procedure is called Pearl Farming.

Pearl Farming

Pearl Farming is now an entire industry, that harvests mollusks like oysters, mussels, and either by nucleation or non-nucleation produces cultured pearls.  Nucleation of oysters produces saltwater pearls and non-nucleated mussels produce freshwater pearls.  The market for pearls now totally constitutes of cultured pearls, natural pearls are rare and if they sell are usually old and family heirlooms.

Pearl Oyster Farming and Pearl Culture

Cultured pearls are grown on pearl farms and the entire process takes up to 2-5 years.  The process begins by fishing for oysters from the sea bed, which is an age old practice.  The modern procedure calls for the collection of sperm and eggs from healthy oysters already present on the farm.  Artificial fertilizing of the sperm and eggs leads to a new generation of oyster larvae. 

The larvae require patient and delicate handling; they are allowed to float freely under water but under monitored conditions.  Over a period of a few months, the larvae develop into baby oysters; they are then transferred to a special area in the farm called a nursery.  Here the baby oysters are tended for 1-2 years till they mature and are ready for grafting.  A mature oyster is pried open delicately and an irritant is implanted in it.  As a response to the irritant the oyster secretes Nacre which coats the irritant and over a period of time forms a pearl. 

Saltwater oysters are nucleated by a bead prepared from a mother of pearl.  The prepared bead is coated with the mantle tissue of another oyster.  This tissue coated bead is then implanted into the oyster’s gonad.  As a defense against the implanted bead, the oyster secretes Nacre which slowly coats the bead to form a pearl. 

Non-nucleated grafting of mussels results in a freshwater pearl.  The mantle of the mussel is implanted with slices of mantle tissue of a donor mussel. 

After the implantation, the oysters are allowed to recuperate and then they are shifted to oyster beds where they are tended till the pearls are formed.  Not all oysters yield pearls, some die, some oysters eject the implanted nucleus, and still others whither away.  Only about 20-30% of the implanted oysters yield pearls.  When the pearls are harvested, they are cleaned dried and sorted.

Pearl Classification

Pearls are naturally organic gems, made by a living being and are mainly classified as Natural pearls and Cultured pearls.

Natural pearls occur in nature when an irritant lodges in an oyster, as a response the oyster secretes Nacre which coats the irritant and gradually a pearl is formed.

Cultured are identical to Natural pearls, but the pearl is formed due to human intervention.  A nucleus is implanted in the oyster to start the process of pearl formation.

Natural pearls are further sub-divided into pearls formed in a seawater oyster host and freshwater mussel host. Seawater pearls are further classified into Blister pearls, Seed pearls and Keshi.

Natural oyster Blister pearls have a flat surface on one side, Natural oyster seed pearls are 2mm in diameter and the Keshi is a natural pearl which forms in a cultured oyster host on a pearl farm. Keshi are generally baroque in shape.

Natural Freshwater pearls are formed in a mussel and are further classified as Blister, seed and pearl.
Cultured pearls are formed with the aid of humans and are also classified as seawater and freshwater pearls.
Seawater oyster host are nucleated with a mother of pearl bead around which the nacre is deposited.  Cultured seawater pearls are further classified into South Sea pearls, Tahitian Black pearls, Blister pearls, Mabe pearls, Akoya pearls, Keshi and Seed pearls.

  • South Sea pearls are 9-16mm in diameter, nucleus is mother of pearl and thickness of the Nacre is 2.5mm.  Pearls are both white or pale pink, pale gray and yellowish.
  • Cultured Tahitian pearls are 8-18mm in diameter; the Nacre is 2.5mm thick, and are usually black, grey or the rare peacock green color.
  • Cultured Blister pearls have a flat surface and are 4-10mm in diameter.
  • Cultured Mabe pearls are 11-17mm thick.
  • Akoya pearls, Keshi and seed pearls are also cultured seawater pearls.
  • Cultured freshwater pearls are produced in mussels and are further classified as River or Karasu pearls, Lake or Sankaku pearls and Seed pearls.
  • River or Karasu pearls are produced by the karasu mussel and are shaped like a wrinkled grain of rice.  They are also known as the Rice Crispy pearls.

Lake or Sankaku pearls are cultured in Japan’s Lake Biwa.  Famously known as the Biwa pearls, they are smooth surfaced with a deep luster.  Biwa pearls come in mind boggling shapes and colors.
Cultured Seed pearls are smaller with a diameter of 2mm or less.

Translation of Pearls

Pearls have been around since history began to be written.  They have been variously used as jewels, currency, as a symbol of wealth, as medicine and also to ward off evil.  Not surprisingly pearls have entered into literature and language, into the Holy scriptures and also used in popular metaphors.

Basically pearls are identified as precious gems, but pearl also has different connotations.

  • A shiny lustered dew drop or a capsule of medicine is termed as a pearl.
  • Pearls of wisdom, a figure of speech, meaning valuable tidbits of advice.
  • A pearl is a 5 point type in printing.
  • Epithelial pearl, in Pathology is a circular mass of keratin in certain carcinomas of skin.
  • Pearl is also a female name.
  • Pearl is the name of a town in Mississippi; Pearl River is the name of a river flowing through Central Mississippi into the Gulf of Mexico.
  • In knitting parlance, pearl is a stitch, pearl edging is the decorative edging on a table-cover or a kerchief.
  • Pearl, is a small sphere of glass containing amyl nitrite, which is to be crushed in a handkerchief and then inhaled.
  • A Pearl eye is an eye with a cataract growth.
  • In literature, Shakespeare writes, “I see thy composed with thy kingdom’s pearls…” “And these pearls of dew she wears” Milton
  • Pearls before swine as quoted in the Scriptures, means to offer something precious to a person who does not appreciate its value.

The usage of pearls in popular lingo, testifies to its popularity in the mind of men and women.  But a pearl, despite its various meanings, first of all means a precious gem which symbolizes purity, innocence and feminine charm.