The Different Pearl Types, Cultured, Fresh Water, Salt Water, Natural and Shell Pearls

Life was simpler when the only pearls came from oysters. An oyster was opened and there, like a miracle, was a lustrous and beautiful natural pearl. Like a gift from the heavens.
Today if you want pearls you need to know the different pearl types. You need to decide if you want real or fake pearls. But what is a real pearl? Today the high-quality pearls available in fine jewelry establishments are called cultured or farmed pearls. The salt water cultured pearls are the most desireable.

Why is a Cultured Pearl Called Cultured?

Cultured or farmed pearls are formed in pearl oysters and freshwater mussels. These oysters and pearls are farmed. Or rather cared for in a defined place in either salt water or fresh water farms. They are in a natural environment, but have been encouraged to create a pearl, by the insertion of an ‘implant’ made from the inner shell of fresh water mollusks and a piece of mantle.
Left on their own, only a tiny fraction of these oysters and mussels would create a pearl. The implant that the pearl farmers insert into the mantle or protective membrane, acts as an irritant and the oyster or mussel surrounds the irritant with layers of calcium carbonate, called nacre.
If you’ve seen the beautiful iridescence on the inside of some sea shells, then you know that a beautiful pearl can have not only luster, but a hint of iridescence.

What’s the Difference Between a Natural Pearl and a Cultured Pearl?

A natural pearl occurs in an oyster, mussel or other mollusk when a calcareous concretion (nacre)  is created to surround an invader, parasite or object.  A natural pearl occurs from a wild mollusk with no intervention from artificial means.

The luster from cultured pearls can vary slightly from pearl to pearl

In the cultured pearl, the implant or irritant than stimulates the creation of a pearl is a particular shape and size. This tends to yield uniform sizes in the harvested pearls. In wild pearls, the shapes are usually non spherical. If you sliced a cultured pearl and a wild pearl and compared them, the wild pearl would have the source of irritation and the balance would be the nacreous substance, in other words there would be a great deal of nacre. In a cultured pearl most of pearl is the spherical implant with multiple thin layers of nacre.

What’s the Difference Between Salt Water and Fresh Water Pearls?

Tahitian cultured pearl in the peacock color

Salt water cultured pearls are made from oysters that live in salt water. Fresh water cultured pearls are grown from mussels in fresh water. For example, Japanese Akoya salt water pearls are usually round. That is the ideal.

Example of freeform shapes of Chinese dyed fresh water pearls

Chinese fresh water pearls tend to be rice shaped or non-spherical in shape. The luster from fresh water pearl often looks softer and different than the salt water pearl’s luster.
Akoya, salt water cultured pearls, need to stay in the oyster at least two years in order to attain the beautiful luster and iridescent look. The salt water oyster can handle the creation of 1 – 2 pearls for each growing cycle. In contrast to the Akoya pearl’s small output, fresh water mussels can handles 40 – 50 pearls per growing cycle.
Salt water pearls, whether Japanese Akoya, Tahitian, or South Sea Pearls, tend to give a deeper luster and hint of iridescence in comparison to fresh water pearls.

What are Shell Pearls?

Shell pearls are so called because they are made of shells. They are made in a lab setting from the mother of pearl inner surface of certain sea shells. Shell pearls are made using a solid mother of pearl inner base to give them a more realistic weight. Their exterior surface is made using powdered mother of pearl. The process of manufacturing them allows for colors like purple and hot pink to be made uniformly by the thousands. Shell pearls are generally uniform in shape. They can be round, oval or any other shape the manufacturer chooses. They are then coated and baked for a sturdier surface than cultured pearls.
Shell pearls are known for keeping their manufactured color, and to be unaffected by perfumes and sweat. Cultured pearls can be damaged by sweat and perfume.
The uniformity of color and shape are one way that you can tell they are not real. And their smoothness is also a hint.

Are Majorca Pearls Real?

Majorca pearls are manufactured, but unlike shell pearls their centers are glass and their finished product stands up to the real thing nicely. They are a high-quality fake.
Like shell pearls, their flawless finish tells you they are not real.

What is a Mabe Pearl?

Mabe pearl with turquoise halo on man’s best friend

In contrast to a round pearl, which is cultured inside the flesh of the oyster, the mabe pearl is cultured on the shell wall of the oyster to create a half pearl. This type of pearl was invented to give women who desired a larger pearl a way to have their dream.

The oyster can only survive a certain size of implant or irritant to cover with nacre. But making a half pearl, the oyster can cover a similar amount of surface without added stress. An advantage of the mabe style pearl, is that it can be worn flat against the ear attractively without bulging forward which it would if fully round.

How to Pick Pearls for Yourself

Multi-colored jumbo baroque cultured fresh water pearl necklace

Pearls have a special allure and have romanced lovers for centuries. The advantage today is the different pearl types available and the vast amount of choices, real and fake. My mission in writing this, was to answer the question, what are shell pearls? Then I remembered how many people have asked me if Majorca pearls are real and so here we are.

Whether you’re rich or poor, subtle or hot pink loving, there is a set of pearls out there for you.

I wrote a blog about selecting cultured pearls. May your pearl journey lead you to pearls that make you look fantastic.

Your Personal Jeweler,
Calla