Rare Finds: Keshi Pearls and Conch Pearls

Lately, I’ve noticed that two relatively unknown pearl types have been making their way into the fashion pages with increasing frequency. Seems that conch pearls and keshi pearls are the new darlings of jewelry designers and stylish celebrities everywhere—and for good reason. They’re absolutely gorgeous! I knew the trend was heating up when questions about these gems began flooding my inbox. Curious? Here’s the lowdown:

Keshi PearlsThe invention of modern pearl culturing in the nineteenth century has made pearls relatively abundant and affordable, which is great news for pearl jewelry lovers. But culturing—the technique of inserting irritants into mollusks to induce pearl formation—is a delicate process, and things don’t always go as planned. Sometimes, the implanted oyster or mollusk prematurely rejects the irritant, but amazingly, the animal will still occasionally create a pearl.

The resulting gem is called a keshi pearl.

Japanese for poppy seed, keshi describes the early gem’s small size. Thanks to the popularity of Tahitian and South Sea pearls, the larger oysters that grow these pearl types produce keshi that are much larger than poppy seeds, but the name has stuck.

Keshi pearls have two important traits: they’re made of solid nacre, and they’re typically non-symmetrical, or baroque. Both traits are attributable to the gem’s lack of a nucleus, but it’s the former characteristic that makes keshi pearls so desirable, because dense nacre results in an intense luminosity—the “inner glow” that makes a pearl valuable. Many keshi pearls also have a rainbow-like shimmer, a beautiful trait known in the gem world as orient. Because they have a luster and orient that is not typically seen in cultured pearls, keshi pearls are increasingly finding their way into fine jewelry designs. If you happen to spot some on your favorite celeb or in a fashion magazine, now you’ll know what they are!

Interesting side notes:

• In the gem world, experts debate whether keshi pearls can be called natural, because, while they are technically non-nucleated pearls, they do result from pearl culturing.
  


• The abundance of keshi pearls may soon decrease, because pearl farmers are working to reduce their occurrence. That’s because the nacre used to form keshi pearls means less of the coveted substance is available to the cultured pearls farmers are trying to produce.
  

Conch “Pearls”Conch “pearls” have also been making a name for themselves in the fashion world of late, so you might be surprised to know that these gems are not really pearls (hence the quotation marks). What the heck are they? They resemble pearls, sure, in looks and in that they’re grown in marine animals, but, unlike pearls, which are made up of nacre—layers of aragonite and conchiolin—conch “pearls” consist of calcium carbonate. For this reason, they are not considered true pearls by gemologists.

Conch “pearls” are found in the Queen conch, a marine animal prized for its beautiful shell and succulent meat. (Walk into any popular Caribbean eatery and you’re likely to find a selection of conch chowder and conch fritters on the menu. Pronounce it conk.) Typically oval or baroque and less than 3mm in diameter—although much larger ones exist—the porcelain-shiny conch “pearls" display the same colors found on the animal’s shell interior: white, tan, yellow, and pink. (A warm salmon-pink is the most popular color and typically commands the highest price.)
A notable characteristic of conch “pearls," but one that not all specimens display, is flaming, or chatoyancy. Described as a silk-like or wet silk appearance and typically only present on the pink “pearls,” flaming occurs because of the way the gem’s layers are structured. Unlike pearls formed with nacreous crystals, conch “pearls” are formed by concentric layers of fibrous crystals. A highly desirable trait, the flame effect is an optical illusion that results from this layered arrangement.

Like real pearls, conch “pearls” are thought to be produced by the animal as a protective measure against an intruder. The “pearls" are a byproduct found by fisherman when the meat and shell are harvested, but the gems are extremely rare. According to the Gemological Institute of America, only one in 10,000 Queen conch shells contains a “pearl," and very few of these are gem quality. Attempts to culture conch pearls have been unsuccessful.
Jewelry lovers who are lucky enough to buy jewelry made with conch “pearls” should know that their gorgeous color fades over time.