Pearls are gemstones which are the product of living creatures. They are formed when an irritant (like sand) is introduced to a Mollusc. Molluscs create a Nacre coating around the irritant which eventually forms the pearl that we see, love and wear. They have been a treasured gemstone for centuries with some records dating back to 2,000BC and are easily recognised as a precious stone as they require no cutting or polishing, easily giving away their beauty and rarity.

Today, most pearls on the market are cultured pearls which means they are not naturally occurring and that the irritant is introduced into the oyster or mussel. The ‘technologists’ then supervise the pearl growth to ensure it is of optimal shape. It makes it easier to match similar shaped pearls for jewellery.

There are many different types of Pearls:

  • Akoya: Salt water pearls grown off the coast of Japan which have a warm colour but rarely reach more than 9mm in size.
  • South Sea: Can grow from 8mm and larger. They are found in a variety of colours such as white, silver, gold and rose.
  • Tahitian: Typically grow from 8mm to 14mm in size. They are famous for their grey and black hues. They also come in red, blue and green.
  • Freshwater: These are grown in mussels rather than oysters and are found in freshwater lakes. They are not perfectly round but are slightly elongated.
  • Mabe: These are less expensive as they are grown against the inside of the oyster shell rather than inside the body. They are generally half round and are used in rings, brooches and earrings.
Lustre and Orient life of pearls chart

Lustre and Orient: 

‘Lustre’ is the pearl’s ability to refract light and ‘Orient’ is the luminosity of the pearls inner glow. The higher the lustre and orient the higher quality the pearl. To observe this, look at the pearl at different angles to see how bright the rainbow reflections shine. The scale ranges from exceptional, fine to dull.
Colour life of pearls chart


There are two elements to consider when you are observing a pearl’s colour- body colour and overtone. ‘Body colour’ is the base colour of black, white or pink etc. However, the overtones include the level of the hue. White pearls with a rose coloured tint are the rarest and most expensive. If the colour is creamy, it will be less expensive.

Size and Shape life of pearls chart

Size & Shape: 

It takes a long time to grow large pearls, therefore it is more common to find smaller pearls. The larger they are the more expensive, but then again it depends on the other factors as well. The more symmetrical the shape the valuable the pearl. The most popular shapes include round, oval and tear shape.

Blemishes life of pearls chart


The creation of a pearl is an imperfect process. Each pearl is unique and the surface may be smooth, other times it may have blisters, spots and small holes. The less imperfections the more expensive it will be.