Pearl Knowledge

Cultured Pearls

Most of the pearls we see nowadays in fine jewellery shops are cultured pearls. Natural pearls are rare or almost extinct and are mainly seen in antique jewellery.

Cultured pearls, like natural pearls, develop and grow within pearl oysters in a natural environment. While the formation of a natural pearl is the result of a small particle accidentally getting into an oyster provoking the growth of nacre around the particle, the growth of a cultured pearl is initiated by man through the implant of a piece of mantle tissue often together with a round shell bead. The oyster envelops the implant with layers of nacre and yields a cultured pearl.

  • Akoya Pearls

The first cultured pearls came from Japan, where the techniques of growing pearls were invented and developed more than 100 years ago.

The pearl oyster species used in Japan to produce Akoya pearls is Pinctada Fucata. These Akoya oysters, which are not bigger than the palm of a hand, yield mostly round lustrous Akoya pearls from 3 up to 9 mm in diameter. They may have a pinkish, silver or greenish overtone.

Similar oyster species are found in China and Vietnam, where Akoya pearls are also cultivated nowadays.

  • South Sea Pearls

In the 20th century, some pioneers adapted and developed pearl growing techniques outside of Japan, in Australia, Myanmar, Indonesia and the Philippines. After an interruption during the Second World War, the South Sea pearl industry experienced significant growth and progress in the cultivation techniques.

Pearl producers found in these oceans bigger pearl oysters the size of a hand and even some as big as a dinner plate. These big oysters named Pinctada Maxima can grow large pearls from 9 to 15 mm for the majority, while exceptional pearls can reach beyond 20 mm in diameter.

Pearls originating from these oceans are called South Sea pearls. Pearl colors depend on the oyster species and the environment they live in. The white-lipped South Sea species yields mainly white pearls with a silver, pink, blue, grey or green overtone. The yellow-lipped species yields cream, yellow or golden pearls.

  • Tahitian Pearls

The pearl cultivation techniques reached Tahiti in French Polynesia in the 1960s. At that time, pearl scientists found in the South Pacific Ocean a pearl oyster species with dark shells known as Pinctada Margaritifera.

These black-lipped oysters give a beautiful range of dark-coloured pearls, from black to brown, grey or silver blue, some with an overtone of red, blue or green.

Those pearls of dark colours, mostly from 4 to 12 mm and some beyond 15 mm in diameter, are usually referred to as Black pearls or Tahitian pearls, although they are also cultivated in other lagoons in the South Pacific apart from French Polynesia.

  • Freshwater Pearls

While Akoya, South Sea and Tahitian pearls are grown in oceans, experiments to grow pearls in freshwater ponds, lakes and rivers started in Japan in the 1920s. The first freshwater pearls were harvested in Lake Biwa in Japan.

Because of industrial development and high production costs in Japan, freshwater pearls are now produced almost exclusively in China.

The pearl mussels used for the cultivation of freshwater pearls, Hyriopsis Cumingii, are white, pink, peach or purple and yield pearls in these pastel colours. Pearl sizes range from 4 to 12 mm in diameter, with exceptional ones reaching up beyond 15 mm.

In contrast to seawater pearls, the growth of most freshwater pearls is triggered by implants of mantle tissue only, without shell nucleus. As a result, the majority of freshwater pearls are fully made of layers of nacre. Unlike South Sea and Tahitian oyster species that can grow only one pearl at a time over a period of 2 to 3 years, Freshwater pearl mussels can yield multiple pearls at once and in a much shorter period of time. This explains their abundance and affordability.

 

Choosing Pearls

Each pearl is unique. Pearls, these beautiful gifts of the seas are the most sensual and feminine gems and can be worn on various occasions by pearl lovers of all ages. To choose the pearls that suit you best:

  • Visit a trustworthy and established jeweller who has a good knowledge of the gem, who carries a wide range of pearls and pearl jewellery for your selection and who can give you an expert’s advice

  • Try several of them on, see which pearl colours match best your complexion

  • Know that all and best pearls are not necessarily perfectly round, white and big, but that pearls come in different shapes and sizes, try several types to see which one you like most

  • Know that pearls' type, size, colour and roundness can vary with personal preferences and budgets.

  • The pearls’ very essence is their nacre and lustre! Try not to compromise on these crucial aspects and rather settle for a smaller size instead if you have to make a choice based on your available budget

  • The rounder the pearl, the bigger the size, the cleaner the surface, the higher the price. Together with the intensity of the lustre and the rarity of the colour these are the 5 factors that command the price