Pearl Varieties and What Makes Them Valuable
Before cultured pearls were invented during the Art Deco period, natural pearls were one of the most sought-after gems around the globe. Now, pearls are much more accessible and undoubtedly strike a note which is just as elegant and refined. While freshwater pearls in various colours and round, coin and baroque shapes are the most abundant, traditionalists may prefer saltwater pearls in Akoya, Tahitian or South Sea varieties, which are available in a classic, round shape and highly-prized hues.
How Were Cultured Pearls Invented?
Natural pearls form when a foreign object gets stuck inside the soft lining of an oyster or mussel. In defence, the mollusk begins to coat the object with smooth layers of “nacre,” also known as mother of pearl. The more smooth, even and symmetrical the layers are, the more natural shine, lustre and value the pearl will have. Diving for natural pearls was extremely strenuous and nearly fruitless, considering that finding an unblemished specimen with smooth, even nacre and a round shape was exceptionally rare—not to mention finding so many you could create a matching string for a necklace or bracelet.
By the late 1800s, many in Australia and Japan, including the famous Kokichi Mikimoto, were experimenting with culturing pearls by inserting their own small objects into various mollusks. Now, nearly all pearls on the market are cultured, but the varieties and price points vary widely based on a number of factors, including: the rarity of their size, shape, body colour and overtone colour, quality and thickness of nacre, and how long it takes to culture each specimen. When evaluating any variety of pearl, you want to look for symmetry, a smooth, blemish-free surface, even body colour and attractive light reflection.
What are Freshwater Pearls?
Most freshwater pearls are sourced from China. To culture a freshwater pearl, a mussel is implanted with multiple pieces of donor tissue, and can produce up to thirty-two pearls per shell. China produces more than ten times the amount of freshwater pearls than all other markets and varieties combined. As a result of this massive volume, even the best quality freshwater pearls are relatively inexpensive when compared to saltwater types, including Akoya, South Sea and Tahitian pearls.
Originally, freshwater specimens were often rice-shaped and very irregular. However, since the 2000s, pearl farmers have been producing gorgeous, round and lustrous pearls of impeccable quality and significant size, some of which can even rival highly sought-after South Sea pearls.
With the resurgence of pearl jewellery, many modern designs have focused on baroque pearls, which are cultured pearls with unique, irregular-shaped nacre. While these interesting shapes were once cast aside, they are now favoured by clients for their more contemporary and modern appearance.
What are Saltwater Pearls?
Akoya, South Sea and Tahitian pearls are all found in various specimens of oysters. These saltwater varieties are cultured by inserting a small bead and a piece of donor tissue from another mollusk into the oyster’s tissue. Each oyster can only produce one pearl, with the exception of Akoyas, which are smaller in size and can sometimes produce up to five. Tahitian and South Sea pearls began to be cultured in the 1950s and 60s and are generally much more difficult to create. Overall, it is an extremely time-intensive process, with single-pearl producing oysters usually having to be two to three years old before they can produce their first pearl, versus the six to twelve month maturity needed to create multiple freshwater pearls.
While Akoya pearls are the smallest of the saltwater group, they are known for their creamy body colour and being the most reflective, with the most prized having nearly mirror-like shine. In their best varieties, Akoyas are also known for having a pink or “rose” overtone, which is the subtle, secondary colour you can sometimes see when light reflects off the surface of a pearl.
South Sea and Tahitians are arguably the most famous of any pearls, mostly due to their amazingly large sizes and beautiful body colours. Tahitian pearls are especially known for having naturally dark and exotic body colours with many possible overtones. Their unique and highly valuable hues are so sought-after that even slight differences in colour can play a very important role in their value. The most valuable pearls of any variety will also display orient, which like overtone, is a beautiful characteristic that many pearls do not possess. Similar to diamonds, orient describes a pearl’s ability to break light down into multiple colours, which gives them an incredibly eye-catching and other-worldly, iridescent effect.