What’s the Difference Between Natural and Cultured Pearls
(Natural Pearl Starter Necklace, photography by Zamier)
Pearls have been prized since ancient times for their natural beauty and their ability to embody timeless style without further enhancement. Symbols of love and glamour, they have been adored and admired by emperors, kings and queens throughout history and across cultures.
Today, pearls have become a staple in nearly every woman’s wardrobe, working just as well with a stylish dress for a night out as they do with a well-worn pair of jeans. Even though people tend to dress more casually than they did decades ago, pearls can still play a role in a daily wardrobe. If you’re interested in learning more about how to wear pearls, even with the most casual outfits, read our blog post “Pearl Manners – How to Wear Pearls in Your Everyday Life”.
If you’re ready to add pearls to your jewelry box and wardrobe, you should first understand the basic differences between the types of pearls before you decide to start an Add-A-Pearl necklace or buy your first set of pearls.
The first, and most basic, distinction to make is natural versus cultured pearls.
How are they formed?
Oysters have a hard protective exterior shell but soft delicate bodies on the inside that need protecting. Oftentimes, small bits of shell, fish scales, or other foreign bodies get caught on the inside shell wall and can’t be dislodged. To protect its soft body, the oyster secretes nacre and conchiolin, which coats the irritant to form a pearl. Nacre is made up of crystallized calcium carbonate or what’s known more commonly as “mother of pearl”. The smooth coating is attached to the irritant by the conchiolin, which acts like an adhesive and is only produced to bond the first layer of nacre to the irritant. Throughout the pearl’s life, the sac continuously expands to form micro-layers of nacre around the irritant, which gradually increases the size of the pearl in a process that takes many years. For example, a natural pearl that is just 4mm in diameter can take an oyster six years to produce.
Where are they found?
The Arabian Gulf was the world’s first source of natural pearls and remained so for centuries. Together with pearls from the Red Sea and the Strait of Manaar, they have been referred to as “oriental” or “genuine” pearls. In fact, this area produced 70-80% of the world’s pearls until the 1950s.
Natural pearls have also been found elsewhere around the world. Click here to read more about where pearls come from.
What type of oysters are they formed in?
Both natural and cultured pearls come from bivalves, which are a family of living shelled mollusks that are made up of two shell halves that open and close for feeding. Most people think that oysters are the only shellfish that produce pearls, but that isn’t the case as both mussels and clams also have the same capability – although it’s much more rare.
What do natural pearls look like?
Natural Pearls tend to be a darker cream color with more hints of yellow or champagne undertones. The luster of natural pearls tends to be deeper although more subtle than the high-gloss luster of cultured pearls. They are also typically more organic in shape, meaning they may not be as perfectly round when compared to cultured pearls.
How rare are natural pearls?
Natural pearls are extremely rare. It’s estimated that one of every 10,000 oysters will produce a pearl spontaneously. Of that number, even fewer will be round and lustrous enough to be usable for fine quality jewelry. In fact, very few strands of matched natural pearls exist. Those that do are often valued at several hundred thousands of dollars.
A large natural pearl is a very extraordinary phenomenon of nature. Their rarity coupled with the rising awareness of their history and value has made natural pearls a rediscovered treasure. The La Peregrina pearl for example, is one of the largest, symmetrical pear-shaped pearls in existence, and was once owned by Elizabeth Taylor. To read more about the most impressive pearls in history, click here.
How are natural pearls identified?
Natural pearls have a thicker nacre or “skin” when compared to cultured pearls. When held against a concentrated light source, a pearl with a thick nacre will show concentric growth lines, where layer after layer of nacre was added over time as described above.
How are they formed?
Although they’re technically formed by living organisms, the creation of cultured pearls is expedited by the simulation of ideal conditions. Pearl harvesters place shell beads inside an oyster, then return the oyster to the water. Over time, the oyster covers the bead with nacre, forming a pearl. Later, the oyster is recovered from the water, and the pearl is removed. Depending on the type of oysters selected for pearl harvesting, different sizes and colorations result. As a general rule, larger oysters produce larger pearls.
Where are they found?
The vast majority of the world’s cultured saltwater pearls are known as Akoya pearls. Akoya pearls are thought of as the classic cultured pearl, because of their consistent roundness and bright reflective luster. They were originally produced in Japan, which has been known as the cultured pearl producing center of the world. Now, China also produces a great deal of Akoya pearls, although their luster is not quite as bright as those produced in Japan.
Other popular types of pearls include Tahitian and South Sea pearls. Tahitian pearls are farmed in French Polynesian, and are naturally black or dark gray in color. South Sea pearls are grown in Indonesia, the Philippines, Australia, and Myanmar, and are light in color. They are typically large in size with a very high luster, making them the most desirable and valuable among cultured pearl varieties.
Pearls can also be farmed in freshwaters, like lakes, rivers, and ponds, again typically in China. They come in a variety of pastel colors, and are generally less expensive than saltwater pearls because they are cultured for a shorter time. Liusa Village in China, also known as “pearl village” boasts 2541 pearl farms. Output from this one village accounts for half of the total pearl production of China. Click here to read more about where cultured pearls are produced.
What type of oyster are they formed in?
Cultured Akoya pearls are formed in the Pinctada fucata (martensii) also known as Akoya oyster. The Akoya oyster is the smallest of the commercially farmed pearl-producing oysters, so it doesn’t usually produce a cultured pearl larger than 9mm. Larger saltwater pearl varieties are formed in larger oyster species.
A saltwater mollusk only produces a single pearl at a time, again contributing to the higher price of saltwater pearls. Freshwater mollusks can grow up to 30 pearls at once, making them much more affordable.
What do cultured pearls look like?
Akoya cultured pearls are known for their perfectly round shape and bright reflective luster. Akoya pearls are considered the classic pearl and are what most people think of when pearls come to mind. They are generally creamy white with rose overtones.
How are cultured pearls identified?
In contrast to natural pearls, cultured pearls have a thin nacre or “skin”. When held against a concentrated light source, cultured pearls appear to have a solid, rounded nucleus with a thin outer layer.
ARE NATURAL PEARLS MORE EXPENSIVE THAN CULTURED PEARLS?
Yes! Natural pearls are considerably more expensive than cultured pearls. One might argue that the reason we have cultured pearls is because natural pearls are more rare and simply cannot meet consumer demand as they need to be formed spontaneously by nature. That being said, natural pearls have regained popularity in recent years. People are drawn to the unique, imperfect perfections of natural pearls. In fact, auction houses have reported that natural pearls are setting records as their value continues to skyrocket. While cut or mined gems are still stylish, they do not carry the same subtle beauty and unique story that goes into each natural pearl.
In comparison, cultured pearls are cultivated on pearl farms in fresh or salt water by people who stimulate the process of pearl creation. As a result, cultured pearls are usually less expensive than natural pearls since they can be produced in greater numbers, albeit in exchange for some of that truly unique process of a naturally occurring pearl.
Since the Akoya oyster is relatively small, Akoya cultured pearls are rare in larger sizes over 7mm. That rarity makes it common to find top-quality Akoya pearl strands retailing for more than $10,000 – much higher than a comparable freshwater cultured pearl.
With all the variation in pearl types and origins, understanding the value of each different type of pearl may seem daunting. The monetary value of pearls is based on four appraisal standards: replacement price, estate value retail, estate value wholesale, and intrinsic value. Click here to read more in-depth about these standards and how they affect the valuation of pearl jewelry.
Although diamonds may be forever, the natural and rare beauty of pearls has been prized for centuries longer than any cut stone. Almost all other gemstones are formed by mineral deposits that must be mined, cut, and polished to reveal their true beauty, while pearls are beautiful as they are. High-quality pearls have a deep rich inner glow that emanates from within the gem, something else that just simply cannot be mimicked in other gems. So whether you decide on natural or cultured pearls, these lustrous jewels are sure to maintain their value, versatility, and beauty.