The Tahitian pearl (or black pearl) is an organic gem formed from the black lip oyster (Pinctada margaritifera). These pearls derive their name from the fact that they are primarily cultivated around the islands of French Polynesia, around Tahiti. Description Tahitian pearls come in a range of colors from white to black. They can contain various undertones and overtones of green, pink, blue, silver and yellow. The most valuable of these are of the darker variety, as the naturally dark tones of the Tahitian pearls is a unique quality among pearls. A true black Tahitian pearl is extremely rare, and largely considered one of the most beautiful kinds of pearls in the world. Most Tahitian pearls that are identified as “black” are actually charcoal grey, silver, or dark green. An advantage of the Tahitian pearl is that the oyster inside of which they grow is quite large, sometimes weighing as much as ten pounds. This means that a Tahitian pearl can more easily grow to a larger-than-average size. The cultured Tahitian pearl comes in various shapes, sizes, and colors; shapes include round, semi-round, button, circle, oval, teardrop, semi-baroque and baroque. Because of their darker hues, Tahitian pearls are commonly known as "black pearls". However, Tahitian pearls have the ability to contain various undertones and overtones of green, pink, blue, silver and yellow. All (or any combination) of these colors may be seen in a cultured Tahitian pearl. Due to the variety of shapes and colors of the Tahitian pearl, it has been known to fit in any jewelry setting. The versatility and mixture of color give it its value. Culturing The culturing process of a Tahitian pearl involves a grafter, who inserts a bead made from a mollusk shell into the gonad, or reproductive organ, of the mature Pinctada margaritifera mollusk. It takes two years for an oyster to mature enough to begin producing pearls. Inserted with the bead is a piece of mantle tissue from a donor mollusk, which influences the color of the pearl being produced and provides epithelial cells to ensure that the oyster produces nacre around the nucleus. The materials used in the process are organic, to decrease the probability of the oyster rejecting the nucleus. The shell is sanded and rounded to form the bead, so the pearls produced have a rounder shape. The whole process takes place quickly, because oysters cannot survive very long