Pearls: The Ultimate Guide | Varieties, Treatments, Carings & More

Next to the glamor of diamonds, sapphire, rubies and the like, pearls can often take a back seat. But the reality is, these divine orbs of beauty are a sumptuous gem in their own right.

They deserve the limelight for once, don’t you think?!

There’s a lot more to the pearl than meets the eye, and a lot worth knowing before you consider making your first (or next) pearl purchase.

Today, we offer the ultimate guide to PEARLS. So buckle up, and let’s get started!👨🏻‍🏫

Pearl Inside a Mollusk on a Beach

What is a pearl, and what is its symbolism?

Highly coveted as a gemstone of extreme beauty for over a millennia, the pearl is born of origins quite unlike any other gem.

Whilst other desirable stones such as diamonds, sapphires and rubies form deep inside the earth under immense heat and pressure, the sumptuous pearl is formed within another living creature!

Freshwater and saltwater mollusks offer a perfect environment for a little pearl to grow and so, pearls are a gem but not a gemstone as they are so often considered to be.

The history of pearls

Throughout this article, I think you will find your jaw drop in awe of the many interesting facts we have to share with you about pearls, but one of the most exciting has to be that pearls were discovered before the time of written history.

What does that mean?

It’s pretty hard to distinguish exactly when and where they were first discovered. But here is what we do know…

A Chinese historian in 2,206 BCE was the first to put pen to paper and record these stunning gems being presented as a gift to Chinese royalty, marking their first appearance in written text.

Other prominent moments in time…
In 420 BC, the sarcophagus of a Persian princess contained a fragment of pearl which began the trend of wearing pearls as a form of jewelry (thank you princess, such a trendsetter!)

And, in the 1st century BC, these pearls became so highly coveted that Julia Caesar passed a law stating that only people of the ruling class were allowed to wear such precious gems (and what he says, goes!)

The symbolism of pearls

The smooth and luscious beauty of these round orbs has gained them many different associations and spiritual idealizations over time. For the pearl, there are many different symbolic meanings depending on the culture and moment in time.

Let’s take a look at a few here!

The moon, water, and pearl symbolism

Many freshwater pearls can be found in a wide variety of shapes and sizes but most commonly, of the saltwater variety are pearls that have a striking resemblance to the moon. The lustrous white spheres have unsurprisingly been associated with the moon across many cultures which is only reinforced by the moon’s connection with the watery home where the pearls are born.

Pearls as a symbol of wealth

As with all things, the rarer the beauty the more value we place upon it. And pearls are not any different. Natural pearls are extremely rare and the search for them has been ongoing for centuries. In ancient times, pearls were worn by the higher classes as a signifier of their status, and even today, we still use the phrase "pearls of wisdom" to refer to valuable advice!

Bridal Pearls

It is no surprise that the glossy white pearl makes for a great gift for a new bride to be with white being a metaphor for innocence and purity. Even in today’s modern times, pearls are often worn at weddings by the blushing bride.👰🏻

The pearl and the journey of the soul

In many ancient Asian cultures, the mystical appearance of the opulent pearl formed from such basic life forms as the oyster, indicates a divine presence. A transformation from a lowly state to one of beauty and perfection. A representation of the soul’s journey to wholeness.

Chemical properties of pearls

Well, we couldn’t round this off without some science now, could we?!

Formed within the soft living tissue of a shelled mollusk, the pearl is a mixture of mineral and organic material. From a chemical standpoint, pearls are composed of 82-86% calcium carbonate, 10-14% conchiolin and approximately 2-4% water.

Okay, now to get into the juicy stuff!

How do pearls form? (Natural and cultured pearls?)

Naturally Formed PearlsCultured Pearls

Natural pearls have got a special place in our hearts because the process of how these little balls of joy come to be is just so incredibly fascinating!

In a process that is entirely different from how other gemstones form, a natural pearl is formed when a foreign object (like a grain of sand, for example) finds its way into a mollusk. It becomes an irritant to the creature inside and so in order to protect itself, the creature releases a substance known as nacre.

Nacre is a silky substance to envelop foreign bodies.

Over years of wrapping the uninvited guest with nacre, the mollusk opens and out pops a glorious pearl. The pearl builds up in layers over time and it all begins…as an unwanted irritation to the unassuming mollusk!

Cultured pearls refer to pearls that are farmed under environmentally friendly conditions.

They are tended to by a pearl farmer (a job title I wouldn’t mind having!) and are grown under supervision rather than being taken from natural surroundings.

The entire process is created to mimic the formation process of a natural pearl. And so, it begins with the farmer placing the irritant (often a spherical bead) into the oyster before popping it back into the water for the oyster to do the rest.

Then it continues on with the natural process of things, covering the irritant in nacre until a shiny pearl forms.

What are the different types of pearl gemstones?

There are two main categories of classifying pearls and below we will take a look at both so you can really start understanding exactly what it is you are buying when it comes to purchasing your very first pearl…

Natural pearls vs. Cultured pearls

The first classification would be natural pearls vs. cultured pearls.

Natural Pearls

Naturally formed pearls are INCREDIBLY rare.💹

It is said that to make only one pearl necklace almost 10,000 oysters need to be taken from the sea-bed. Because of this they almost disappeared from the market entirely in the late 1800s because of over-harvesting.

Nowadays, most natural pearls are family heirlooms of celebrities or the incredibly wealthy. Mostly sold at auctions, we rarely see them in the marketplace.

Famous natural pearls in the world

The La Peregrina Pearl

The La Peregrina Pearl is one of the most famous natural pearls in the world! Reports suggest that it was found close to the island of Santa Margarita in the Gulf of Panama in the mid-16th century.

Approximately 17.5mm by 25.5mm and weighing over 11 grams, this extraordinary pear-shaped pearl was one of the largest to be found!

The Hope Pearl

The Hope Pearl is just another exquisite example of a famous natural pearl. This natural saltwater pearl was believed to be the largest saltwater pearl ever to be found. Named after Henry Philip Hope, this Anglo-Dutch gem collector was known for his renowned diamond and gemstone collection.

Weighing approximately 1,800 grains (equivalent to 450 carats), the Hope Pearl is what is considered as a blister pearl, having formed on the inner surface of the mollusk shell.

Cultured Pearls

...Over 99% of pearls sold today worldwide are cultured pearls…

Yes, natural pearls are not only incredibly rare (which makes them come with a significant price tag) but they are arguably not overly environmentally friendly with the amount of diving and acquisition it takes to make even one single necklace!

Because of this, most pearls on the market are cultured pearls.

Saltwater pearls vs. Freshwater pearls

OK, let’s quickly distinguish the difference between saltwater pearls and freshwater pearls, shall we?

  • Saltwater pearls are formed from oysters within oceans often found in places such as Japan, Australia, Tahiti, Indonesia and Thailand (I know, very exotic!). The saltwater pearl often takes longer to develop than that of a freshwater pearl and therefore demands a higher price.
  • Freshwater pearls however, are grown in freshwater sources such as rivers and lakes. For the most part, these freshwater pearls are mainly grown in China but some may be found in Japan or the USA.
Steven KwokIGI Certified Pearl Grader
Do make the mistake that so many people make in believing that freshwater pearls are cultured pearls whereas saltwater pearls are natural.

This is simply not the case!

Natural pearls are incredibly rare and so both freshwater AND saltwater pearls are cultured.

Major saltwater pearl varieties on the market today

Akoya Pearls
Strands of Japanese Akoya Pearls

Akoya pearls are saltwater cultured pearls from the Pinctada fucata oyster. In the cold saltwater of the Pacific Ocean just off the coast of Japan, these beauties are thriving! It can take up to 18 months for the highest quality of Akoya to form, harvested in the colder months for the greatest thickness of nacre.

The Pinctada fucata oyster is a considerably small oyster to produce such pearls, measuring only 3 to 5 inches in diameter. Because of this, the pearls it produces are also smaller than other saltwater varieties—forming pearls approximately 2mm-8mm in size.

If you’re looking for extraordinary luster and a perfectly round shape, the Akoya pearl is for you! The consistency of tone and color make them an excellent choice for fine jewelry!

Where color is concerned, the Akoya varies in shades from white to white-pink. (Although pure white varieties are harder to come by!)

South Sea Pearls
Golden South Sea Pearl Earrings on a Mother of Pearl Shell
Golden South Sea pearl earrings

The Pinctada maxima is the oyster in which the South Sea pearl is cultured. In the ocean between the Indian and the pacific is where this saltwater pearl is often found.

The largest type of cultured pearl, the South Sea pearl can be anywhere between 8mm and 16mm in diameter! Bead nucleated, they can take roughly 2-3 years to grow and their round/symmetrical shape has a soft and silky appearance.

The silver-lipped oyster (cultured on the coasts of Thailand to Australia) typically produces white pearls with overtones of silver, pink or blue.

Whilst the gold-lipped oyster (grown off the coasts of the Philippines and Indonesia) produces a golden pearl with varying hues of yellow and orange.

Tahitian Pearls
Round Tahitian Pearls

Tahitian pearls are something exotic to be sure.🏝️ From the Pinctada margaritifera or BLACK-LIPPED pearl oyster, are the Tahitian pearls.

They are grown in French Polynesia and despite them often being described as black pearls, the term black is actually used to describe the dark body color. They are never truly black.

In the overtones of these dark beauties, we see colors of blue, purple, green, brown and silver. Similar to other cultured saltwater pearls, Tahitian pearls are bead-nucleated. They come in a variety of shapes including—round, near round, baroque and circled.

The exotic appeal of these dark globes makes them highly sought after for those looking for something truly unique!

Abalone Pearls

Now here’s something I bet you never thought you’d here—unlike the pearls mentioned above, these pearls are formed within an abalone instead of an oyster.

Famed for their iridescent colors, abalone pearls are the most colorful and intriguing. The demand for this particular pearl isn’t quite so high due to its often irregular shape yet, the highest quality of abalone pearls can cost a pretty penny!

Their vibrant colors and unique shapes certainly set them apart from the rest. They can grow up to 5cm or more in length and up to 2cm in width with some measuring well over 50 carats!

The abalone pearl, though beautiful and characterful in its own right, can be very fragile. They can be easily damaged if not well looked after and so for everyday use, they are not recommended.

Freshwater Pearls

Freshwater pearls are generally grown in Hyriopsis cumingii mussels and can be either nucleated or non-nucleated. Round non-nucleated freshwater pearls are pretty hard to come by; they tend to appear in non-spherical or irregular shapes. As the cultivation techniques advance, nucleated pearls increase their share in the freshwater pearl market, and they become closer to the round or near-round shape with a diameter ranging from 4mm to over 10mm.

The body colors of freshwater pearls are white, pink, orange or purple with an overtone of yellow, blue, green or pink. On average, freshwater pearls have thicker nacre than saltwater pearls, making them more durable.

The pearl quality factors: A guide to evaluating the beauty and value of pearls

Most pearl grading systems that you will come into contact with are based on the below 7 factors.

These 7 aspects of a pearl are what we can use to distinguish its quality and value. You might think, "Well, a pearl is a pearl is a pearl!" But there is much more to it than that…✍🏻


With all other aspects being equal, as always, bigger usually means better. And the pearl is no different! The value of the pearl is dependent on all 7 criteria and so, where size is concerned the type of pearl must be taken into account. However, in most cases, even an increase in size by 1mm can create a substantial markup in price.

The lesson here? Size matters!


Pearls can be formed in all sorts of fabulous and interesting shapes that we have very little control over due to their organic origin. Believe it or not, although round pearls are the ones we see most often, they are in fact quite rare!

Pearl shape is usually divided into three broad categories based on overall characteristics:

  • Spherical shapes - which are perfectly round or near to perfectly round.
  • Symmetrical shapes - a pearl of any shape that is balanced and regular. Sliced down the middle both halves would be identical and matching
  • Irregular shapes - Irregular or abstract shapes that are non-symmetrical.

These shapes can also be broken down again into these subcategories:

  • Round
  • Near-round
  • Oval
  • Button
  • Drop
  • Baroque
  • Semi-Baroque
  • Circled
  • Keshi

In general, round pearls are more valuable due to their rarity with symmetrical shapes considered more sought after than the abstract shapes of the baroque pearls or keshi pearls, for example.


There are usually three main components to consider when determining the quality of a pearl’s color:

  • Body color - the main dominant color of the pearl
  • Overtone - one or more translucent colors that are present on the surface of the pearl's body color
  • Orient - Iridescent or rainbow-like colors that shimmer on or just below the surface of the pearl

Generally, the popularity of specific pearl colors at any given time is what will dictate the rise and fall of prices. Trends play a big part in the demand for certain colored pearls!🔍


Luster may well be the most important of all 7 pearl quality factors. Luster is what gives a pearl its unique beauty, a combination of brilliance and glow. There are five main categories of luster:

  • Excellent - The pearl’s reflection appears bright, with a strong glow
  • Very Good - The pearl’s reflection appears bright with a near sharp glow
  • Good - Reflections seem bright but not overly sharp. A slight haziness and blur to the edges
  • Fair - The pearl appears dull and reflections are weak
  • Poor - Reflections are dim

With all else being equal, the greater the luster, the more valuable the pearl!

Surface Quality

Like any other gem, the quality of the pearl must also take into account any surface blemishes or abrasions that affect the look and durability of the pearl.

There may be apparent scratches, creases or wrinkles that don’t affect the shape too much. However, if these characteristics are more severe, they could affect the durability of the pearl which makes it at a higher risk of damage.

Ideally, the smoother and more flawless the surface quality, the better.

Nacre Quality

Nacre is the silky wrapping that has coated the nucleus of the pearl. It is closely related to luster in many ways. If we can see the nucleus of the pearl through the nacre, or if the pearl has a dull or hazy appearance, it can be assumed that the nacre is thin.

A thin nacre can create a lack-luster pearl and can also be prone to damage. Not ideal!🙂


For a beautiful pair of earrings or a staggering pearl necklace for a bride-to-be, jewelers are often looking for pearls that match in all quality factors. So, when purchasing jewelry with multiple pearls, the 7 quality factors matter across every one of them!

What should you know about pearl treatments?

So, we’ve learned that natural pearls are incredibly rare and that most pearls found on the market today are in fact cultured pearls.

For the most part, this means that many pearls found on the market today have been treated in some way to enhance their natural beauty and make them truly stand out for your jewelry pieces.

Here are some of the most popular pearl treatments:

  1. Cleaning - Although considered a treatment, is it really? Technically, yes. Whilst it would be nice to imagine that pearls are taken from their mollusk home dazzling and perfectly shiny ready to sell, they are often covered in dirt and polyps. The cleaning process of all pearls is pretty standard!
  2. Bleaching - Bleaching is used to lighten the natural body of the pearl. Sometimes, with pearls of thin nacre, coatings of protein conchiolin (which is very dark) that surround the nucleus can be seen through the pearl nacre. Bleaching hides this darker color of conchiolin.
  3. Polishing - Most pearls, bleached or otherwise will be polished to enhance their luster and smooth out any imperfections on the surface of the pearl.
  4. Dyeing - Does exactly what it says on the tin! A chemical dye is used to give pearls a specific tone such as the pink color that is so very popular at the moment.
  5. Heat Treatment - Heat treatment is used to enhance the natural luster of the pearl.
  6. Irradiation - Most often used on Akoya pearls and light-colored freshwater pearls, irradiation gives pearls a darker and richer tone.

Must-read: How to care for pearls?

Whilst the beloved pearl has many fine qualities, they rate quite low on the Mohs scale of hardness. Because of this, it’s super important we know how to care for them so they last us a lifetime!🧼

Here are our top tips!

  • Wear them often - pearls were born in water and so we want to avoid them drying out over time. The natural oils your skin secretes and the water in the air around us mean that they want to be worn! And they will be better off for it!
  • Gently wipe with a soft cloth after every use - this is to remove any chemicals, excess dirt or build up before putting them away.
  • Do not store in an airtight package - remember, pearls need moisture and so if you keep them in an airtight bag or container they will quickly dry out and lose their luster.
  • Keep them separate from your other jewelry - being softer than most other gems, pearls can easily be scratched by other jewelry, stones or metal…so keep them separate!
  • Last to go on, first to come off - add your pearls to your outfit as a final touch. Make sure they go on after any lotions, perfumes or hairspray you might add.
  • Do not submerge them in water! - be sure to take them off when washing the dishes, having a shower, going for a swim…the chemical in the washing up liquid, shampoo and chlorine in the pool will damage your precious pearls.

How are pearls used in jewelry?

I’m so glad you asked!

Top categories of pearl jewelry

Pearl necklaces and pearl earrings are the top two categories of pearl jewelry on the market today.

Due to their low durability, rings and bracelets (though there are plenty about!) are at higher risk of damage. Whilst a necklace or earring set can be worn on the safety of one’s neck or earlobes.

Mix ’n’ match

A combination of colors, shapes and sizes can be combined together to make a fantastic collection of unique and characterful pieces.

With so many varieties on offer, the world is truly your oyster (excuse the pun!) where pearl jewelry is concerned.

Pearls and other gemstones

And if you want to take things even further, you can combine a lustrous pearl with other gemstones to create a truly exquisite piece.

A stunning bright pearl would be truly magnificent sitting in the center of a diamond halo as a pendant or drop earring set.✨ The colorless diamonds would be sure to enhance the glow and reflection of a smooth white pearl, and vice versa!

Do men like pearl jewelry? Is men’s pearl jewelry trendy?

Well, now isn’t that a question and a half!🤪

It’s true, the pearl has until recent times been viewed as a feminine gem. Worn by the likes of Audrey Hepburn, Princess Diana and Elizabeth Taylor.

The list of celebrity royalty to have donned the pearl is endless. Yet, men are now being drawn to the character of the pearl. Paving the way for men, we now see icons like Harry Styles, Alessandro Michele at Gucci and Pharell Williams proudly wearing pearls as their jewelry of choice.

In a world where it is becoming less fashionable to assign specific genders to our objects of affection, it seems that even pearls have a place in the male wardrobe!

Everything you need to know about pearls

There is a lot of information to take in here! The truth is, pearls are possibly one of the most intriguing gems out there, they truly are in a world of their own.

And whilst most found on the market today are cultured pearls, they are no less exquisite and their history no less fascinating.

When buying pearls, as always it comes down to personal preference. So perhaps you prefer an odd-shaped pearl, with lumps and bumps and an extraordinary display of color…or perhaps you enjoy a classic round, white pearl (Like the ones we see in the movies).

Whichever it may be, there is a pearl to fit every personality, you just have to go find it!

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