Various types of pearls

MASAYUKI KATO / Wikimedia Commons

Pearls are some of the most expensive gems on the market, with an amazing history and impressive cultivation process.

Known as the oldest and one of the most desired gems in the world, a beautiful pearl symbolizes wisdom, integrity, and loyalty. But the history of pearl’s creation is perhaps one of the most fascinating tales you’ll ever come across. Let’s dive into the world of pearls, how they were created, what are they made of, the different types, the harvest process, and a lot more. Diamonds may be a girl’s best friend, but pearls are indeed her one true soulmate.

What is a pearl and how is it made?

Most of us know what a pearl looks like on the outside. It’s a round, smooth, glistening object, known to be rare and extremely valuable. You can also find other shapes of pearls, often known as baroque pearls – in fact, a perfectly round pearl is known to be extremely rare. There are also many types of pearls, from natural to imitation, saltwater to freshwater.

A pearl’s life starts in an oyster. An oyster has a layer of material that protect its organs, known as the mantle. In order to further protect itself from parasites or bacteria, an oyster creates layers of a mineral substance called nacre, also known as the Mother of Pearl. However, it’s important to not confuse the Mother of Pearl with the actual gem. In jewelry, Mother of Pearl is a thin coating of the pearl, giving the gem a lustrous effect. In order for a pearl to be formed, an oyster must create several layers of nacre.

Group of oystersGroup of oysters
 David Monniaux, mod. by Peter Gugerell / Wikipedia Commons

Still confused about the whole process? Let’s break down what an oyster actually looks like to make it easier. The oyster’s shell has two parts, which are connected with ligaments that allow it to open.

On the inside, the oyster has a mouth, stomach, heart, intestines, gills, anus, abductor muscle, and mantle. The mantle is in charge of creating nacre – it takes minerals produced by the oyster’s food and creates the Mother of Pearl, aka nacre. However, it’s important to note that not all pearls go through this same production process.

In the next section, we’ll examine the different types of pearls and what makes them unique.

Natural/wild pearls

Natural pearls are also known as wild pearls – they’re extremely rare and therefore can be sold at higher prices. As previously mentioned, they’re formed when an irritant enters the oyster. The oyster then uses protective layers called nacre to coat it, which eventually forms the gorgeous pearl luster. The pearl formed is round and smooth.

Cultured pearls

A cultured pearl has a similar process with a slight difference – the irritant, perhaps a piece of shell or a bit of sand, is entered manually. It takes at least three years for the nacre to shape the pearl in order to deliver the quality that could potentially rival one created in a natural process. A lower quality pearl often results in the rushing of this process, creating an overly thin nacre coat. It is reported that only 5% of cultured pearls are able to imitate the natural quality. However, lower-quality pearls can be sold for almost as much as cultured due to the inability to know the difference.

Imitation pearls

On the other hand, imitation pearls are entirely fake. They are made from a regular bead that gets coated in a fish scale solution to resemble the shiny surface of real pearls. However, this pearl’s coating is extremely thin and can easily wear off. The usual rule of knowing whether you’re holding an imitation pearl or not is to slide them along your teeth – natural pearls will remain completely smooth on the surface while imitation pearls will not. Imitation pearls may come under many names, including Mallorca pearls, costume pearls, and pearl beads. They will also be notably lighter than real gems.

Akoya pearls

You’ve probably heard of Akoya pearls before – they’re one of the oldest and most-known saltwater pearls out there. Their history began with Kokichi Mikimoto, the father of saltwater pearl cultivation, an industry that dates back to 1800. It took him twelve years to successfully cultivate his very first round pearl. His techniques were soon adapted by people from around the world and pearl-making became widespread, especially in Japan.

Mikimoto Pearl Island in Toba, Mie, Japan
Mikimoto Pearl Island in Toba, Mie, Japan
Mikimoto Pearl Island in Toba, Mie, Japan Wikimedia Commons (CC BY 2.0)

The country became known for its superior Akoya oysters and the leading pearl cultivator in the industry. They combined attention to detail with passion and created the most wanted gems in the world, called the Akoya pearls.

The harvesting process remains the same as usual, but Akoya oysters are the most costly to grow. It takes up to 18 months for them to be ready to harvest from the initial nucleation process. Less than 5% of Akoya oysters produce high-quality pearls, but their chance of doing so remains the highest from any other type of oysters. They are also rumored to produce the most luster. It’s precisely why the most pearl necklaces out there are made of pearls cultivated from Akoya oysters. Good quality saltwater pearls need to be more than 20 years old. But of course, every industry leader has to have competition. 

Freshwater pearls

Alongside Akoya, freshwater pearls also tend to be commonly produced. It’s known that a freshwater oyster is capable of producing up to 30 (with 50 mentioned on some accounts) pearls at a time, which speeds up the entire jewelry-making process. However, despite being widely used in the industry, they have a slight difference to its competitors. Its luster isn’t as glossy as the one you may find in Akoya. The quality doesn’t compare, however, it creates a much more affordable pearl jewelry.  

Freshwater pearls come in many colors, as well as baroque shapes. They are produced and mass-harvested in China. Due to the many shapes, they also need to be carefully matched – any loose pearls found are sold separately.

South Sea black pearls

Of course, pearl cultivation doesn’t only occur in Japan and China. This is why you can find some of the rarest gems in other parts of the world. One such example is the South Sea black pearls, which grow in black-lipped oysters. However, you can’t find them everywhere – they can only be found in Tahiti. The pearls can be slightly larger than others and feature black color with a beautiful green undertone. Another version of the black pearls is the Cortez pearls, which can be found in Mexico’s Sea of Cortez area. They are dark green with rose and gold overtones.

Black pearl in shell
Black pearl in shell
Black pearl / Wikimedia Commons / (CC BY 2.0)

Tahitian pearls

Tahiti shores also grow the South Sea gold pearls, which are produced in a gold-lipped oyster. They’re considered the rarest of all. Another rarity is the South Sea white pearls.

Tahitian pearls
Tahitian pearls
Tahitian pearls Wikimedia Commons (CC BY 2.0)

You can find them in several areas, most commonly in Australia, Burma, Okinawa, and Indonesia. They tend to be the largest of all pearls and are mostly creamy white.

Pearls in world history

While Kokichi Mikimoto created the cultivation industry, it is believed that pearls were first used while ancient villagers foraged the shores for food. Pearl jewelry from 420 BC indicated oysters have been knowingly or unknowingly harvested for quite some time. The gems were often used as gifts to Chinese royalty and many other cultures considered them an important status symbol.

They became so popular they were limited to a specific society – for example, Julius Cesar created a law that only allowed the ruling class to wear them. They were so highly valued they became a subject of plenty of legends and mysteries. A Chinese legend believed pearls were a part of a dragon’s head and in order to get to them, you have to slay a dragon. Persians were convinced pearls were so beautiful they were formed when a rainbow met the Earth after a storm.

Collecting pearls wasn’t an easy job back in the day – divers had to search for oysters and the job was tedious. Not only was it time-consuming to find the oysters, but it was also extremely hard to find quality pearls to begin with. Of course, it was much easier to search for mollusks in shallow areas, but that was often reserved for the royals and high society members.

Overall, pearls remain one of the most wanted and expensive gemstones in the world. Their history is unique and impressive, as is the cultivation process. Should you be looking to purchase pearls, it’s always best to remember the types and features to determine you’re getting good value for your money.

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