Pearls – A guide

Pearl were once believed to be drops of moonlight that fell into the sea and were eaten by oysters, or to be tears of angels fallen to earth. They have been collected by man for as long as people have gathered shellfish. Originally they were adornments of Gods and Monarchs, they were the symbols of wealth and good fortune. They range in size, shape and colour, and the finest examples can fetch astronomic sums, however the introduction of cultured pearls in the early 20th century made pearls available to the wider public for the first time.

Pearl formation

They form accidently, when a grain of sand enters the oyster. If the oyster cannot expel the sand, it protects itself by secreting layer after layer of a substance called nacre, which covers the sand. This becomes the nucleus of the pearl, which will continue growing for as long as the oyster lives.

Pearls in History

Throughout Greek and Roman times, pearls were used in temples to honour their gods, placed on statues and offered up as gifts. The interior of the Temple of Venus was decorated with pearls. In her seduction of Marc Anthony, Cleopatra was said to have taken a pearl from her ear, crushing it and drinking it.

In Europe, Queen Elizabeth I had an insatiable desire for pearls, and owned at least 80 wigs and over 3000 gowns, all encrusted with them. In later times, Empress Eugene and Queen Victoria both adorned themselves with pearls. In 1917, Pierre Cartier paid for his Fifth Avenue shop in New York with a two strand pearl necklace, which still stands as Cartier’s American headquarters.

One of the most famous pearls in history, “La Peregrina”, is a pear shaped white pearl, found in the Gulf of Panama in the 16th century. It was owned at different times by Phillip II of Spain, Mary Tudor (daughter of Henry VIII), the Marquise of Abercorn, and finally by Elizabeth Taylor.

Cultured Pearls

Through most of history, pearls only formed naturally, and so were immensely rare.In the late 19th century, a Japanese man called Koichi Mikimoto perfected a technique whereby oysters could by induced to create pearls. This opened up pearls to the mainstream market. In the mid-to-late 1940s, following the second world war, pearls were sent back to America by US soldiers stationed in Japan, which was a significant step in the popularisation of cultured pearl jewellery.

Pearl Quality – the 7 factors

In the same way as there are the 4 Cs for diamonds, there are seven factors to bear in mind when grading pearls. They are

  • Size of pearl
  • Shape of pearl
  • Colour of pearl
  • Lustre of pearl
  • Surface Quality of pearl
  • Nacre Quality of pearl
  • Matching of pearls

Size: Quite simply, larger is more valuable!

Shape: Generally, pearls can be classified as Spherical, Symmetrical or Baroque. Each of these three have further subcategories.

Spherical can be either Round or Near-Round, where Round is more valuable. Symmetrical can be Oval, Button or Drop shaped. Baroque is irregular shaped, and is divided into Semi-Baroque and Baroque, for either slightly irregular (Semi-Baroque) or highly irregular (Baroque)shapes.

Colour: Pearls occur in a wide range of colours, and can also be dyed to make colours which do not occur in Nature. Colour is comprised of 3 factors, the body-colour, the overtone, and the Orient. The body-colour describes the overall colour. The Overtone is one or more colours that lie over the body-colour. The Orient is the rainbow sheen or shimmer seen on or just below the surface of a pearl. All pearls have a body-colour, but not all have overtones or Orient. The “Best” colour is a matter of taste, there is no right answer. In general terms, white to pink-white tend to command higher prices.

Luster: Luster describes how “shiny” the pearl is, and is the most significant factor in determining the value of the pearl. The luster ranges from Excellent, with bright and sharp reflections visible on the surface of the pearl, to poor, where the surface barely reflects anything.

Surface Quality: Most pearls have some surface blemishes, formed naturally within the oyster. Perfectly smooth pearls are rare, and hence more valuable.

Nacre Quality: Perhaps a more technical factor, the thicker and more uniform the nacre, the better the pearl.

Matching: A well matched string, with no significant variation from one to the next is more valuable than a string with lots of different pearls.

Caring for Pearls

Pearls are soft, and can easily be abraded. They should be protected from contact with other metals, such as chains and brooches. (And anything else found in jewellery boxes!) When stored, pearls should be placed in a protective pouch or bag, to avoid contact with sharp objects. They should be stored away from sources of heat or light. Pearls should also be cleaned periodically, even if not being worn Never clean them with any product. They are best cleaned with a soft cloth. Water can damage the string, weakening the knots. When wearing pearls, never put any chemicals of any description near them; this includes perfume, tanning or body lotions, cosmetics or hair spray.