Black Pearl

Pearls are a striking and coveted gemstone made by certain species of mollusks, most commonly oysters.  For centuries, they have been harvested around the world by ‘pearl divers’, skilled swimmers that dive upwards to forty meters in depth to pluck oysters from the seabed.  Whether or not the oyster they retrieved had a pearl in it was pure chance, and the odds were definitely stacked against them.  Different species of oysters produce pearls at different rates, but in a sample of three tones of oysters it is not uncommon to see only three or four perfect pearls.  This has made pearls a very valuable commodity for many years.  Black pearls, which come only from a specific species of oysters found in Polynesia, were especially rare and thus extremely valuable.

More recently, however, a technique was developed to virtually guarantee pearl production in oysters, and pearls today are farmed in large numbers throughout the world, including black pearls.  An oyster produces a pearl in response to a grain of sand or other contaminant finding its way inside their shell.  As a sort of ‘immune response’, the oyster reacts to the intruder by calcifying it, or covering it in thick layers of calcium carbonate.  The result is usually a spherical shape of the substance we call ‘mother of pearl’.

By inserting irritants such as sand into oysters, it dramatically increases the odds of pearl production.  Essentially, an oyster farmer does just that.  The resulting pearls can take up to six years to be made, but they can be counted on in large numbers.  Since not all of them are perfect, and they take so long to make, pearls are still a valuable gemstone.

The color of the pearl varies depending on the species of oyster, but strongly correlates with the color of the outside shell.  Most species of oysters, including the popular kinds harvest for pearl production in Japan and Australia, are white or of an off white color.  Various hues exist, including yellow, blue, brown, green and red.  Black pearls are still found exclusively from the species ‘Pinctada margaritifera’, which are native to the Tuamotu lagoons of Polynesia.  Though these pearls are also made in large quantities today, they are in fashion in Europe and thus are quite expensive from the demand.

Fashion styles and demands aside, today the value of a pearl has more to do with the size and luster of the pearl than its color.  A black pearl that is more green than black but has a strong luster and a good shape will be much more valuable than a straight black pearl lacking in luster and with defects.

Made into necklaces, earrings, bracelets and many other kinds of jewelry, pearls make an excellent gift, and are a beautiful product of nature.