Let us remember that pearls are one of the most coveted precious stones in the world, so much is their fame that various methods have been created to create different types of pearls and countless varieties have been discovered. Pearls are the most storied group of organic gemstones in mankind.
First of all, we must remember how a pearl is formed.
How is a pearl formed?
A pearl is formed when an intruder that can be a grain of sand, a piece of quartz or even a pearl enters the oyster or mussel, then the mollusk covers this intruder with concentric layers of nacre around it, thus forming a bag of pearls This is basically a defense reaction that the mollusk makes.
Now, with this introduction we can already understand how the different types of pearls are classified.
Classification and types of pearls
In general, there are two large groups of pearls, being the following:
- Natural and cultured pearls
- fresh and salt water pearls
Natural and cultured pearls
The natural pearls They are those that have been formed without the intervention of man, that is, they are those in which the mollusk has generated pearls inside as a defense mechanism. This group of pearls are very rare and therefore their market value is high..
The cultured pearls are those that are manufactured with the intervention of human activity, in this case various techniques have been created to cultivate pearls inside molluscs, but nothing ensures that this process is successful, in fact, only 5% of cultured pearls reach succeed so they are still valuable.
Regarding the characteristics and properties of natural and cultivated stones, they are practically identical, so there is no distinction to inexperienced eyes.
Fresh and salt water pearls
This classification is very simple, basically pearls are distinguished according to the formation environment, whether in fresh water (rivers and lakes) and salt water (oceans).
The freshwater pearls They are those that grow inside mussels that live in rivers and lakes that are generated within the continents. One condition is that the waters are relatively calm and the formation of the gemstone is similar.
The saltwater pearls They are those that grow within mollusks that grow within the oceans, in general this type of pearl is usually a little larger than freshwater pearls.
Pearl types
Next, we show all the types of pearls included in the aforementioned groups.
South sea pearls
The pearls of the south seas They are very valuable because the oyster only produces one pearl in its lifetime. They are characterized by having an average diameter of 9 to 16 millimeters and because they have formed in oysters that have white, silver and gold lips.
Thus, the typical colors of these pearls are clear, that is, they are white, silver, pale pink, light gold, even intense orange. These gems are found in Australia, New Guinea, the Philippines, Indonesia, Burma.
Tahitian pearls
The tahitian pearls They are characterized by having a diameter between 8 to 18 millimeters, their typical shades are dark, ranging from gray, black and dark green. Very rarely they produce clear pearls such as yellow or pink. These types of pearls occur in French Polynesia, Mexico and Panama. They are also considered valuable gems since each oyster produces a maximum of two pearls in its life.
Akoya pearls
The akoya pearls They are characterized by having between 3 to 10 millimeters in diameter. These types of pearls need prior treatment to form because oysters must be at least 3 years old before they can begin to form pearls.
The natural colors of these gems range from pale blue to deep blue, sometimes with bluish-grey hues. From time to time, they usually present pink and gold hues.
These stones can be found in Japan, China, Vietnam, Thailand, and Australia. Each oyster only produces one pearl in its lifetime.
Pearl rainbow lips
The pearls with lips rainbow farms are special because there are only two farms and one of them is in the Gulf of California. They usually have a diameter between 8 to 9 millimeters and their authenticity lies in the fact that they have colors similar to a natural rainbow. Also, on pearl farms it is common for the pearl to be given the same name as the person who farmed it.
It is worth mentioning that the oyster only produces a single gem in its entire life, giving these precious stones added value.
Mabe pearls or composite pearls
The Mabe or Composite pearls They are characterized by the fact that they are formed by the union of half a mother-of-pearl sphere with a shell, thus concentric layers of mother-of-pearl are formed on the mother-of-pearl sphere, creating a pearl dome. After this process, the dome is cut, separating the generated pearl.
For its duration, care and finishes, the pearl dome is filled with resin and mother-of-pearl. These types of stones are used for earrings, brooches or pins.
Baroque pearls
The baroque pearls They are those that have an irregular shape and are not completely spherical, they can vary from oval, curved or even in the form of accumulations of lumps. These stones are thus formed when the organic material that forms the gem decomposes naturally and gives off gas. This gas swells the faces of the pearls between the layers of mother-of-pearl.
Keishi Pearls
The keishi pearls They are almost irregular in shape and are made entirely of mother-of-pearl. These gems are formed when the oyster rejects the irritating material or nucleus that humans try to introduce into the oyster, but the mollusk still produces nacre, creating a small pearl without a nucleus.
Freshwater pearls
Freshwater pearls are those that form in the calm water of rivers and lakes from mussels. These stones do not usually have a defined size, in fact, their size will be larger the longer they spend inside the mussel.
The colors of these gems are usually white, cream, pastel shades, pink and purple. Although, if natural freshwater pearls have been found, they are very rare, so most are cultivated by humans.
Almost all cultured freshwater pearls come from China. Mussels can produce between 6 and 120 pearls during their lifetime, which is impressive.
In this group of pearls, there are two subgroups, the seed beads which may be at least 2 millimeters in diameter, and the biwa pearls Originally found in Lake Biwa in Japan but now cultivated in China, these pearls have a characteristic deep luster.
Natural pearls
The natural pearls They are those that have been formed without the intervention of the human being during the process, this type of pearls are usually spherical in shape, although it depends on the life of the mollusk, some are irregular.
They usually occur when, for example, a larva pierces the shell of the mollusk, it dies and activates the self-protection mechanism that begins to produce the mother-of-pearl that covers the foreign body as a self-protection, generating a beautiful pearl.
The colors of the pearls can be white, soft pink, mauve, brown and pale gray, these colors depend on the composition of the pearl, which are basically carbonates.