If you are interested in purchasing a Tahitian black pearl necklace, the nacre thickness should be the first thing you pay attention to. However, there are many other factors that affect the quality and price of the pearls you are buying. It is important to know these so you can choose the best necklace possible for your available budget.
Luster – a high quality Tahitian pearl will always have a beautiful luster, which refers to the pearl’s ability to reflect light. A pearl with a thick nacre will usually reflect light similar to that of a mirror, meaning you can see the reflection of things in the pearls. Tahitian pearls, because of their color, have a sheen with a slight resemblance to metal, and look much more like a mirror than a typical pearl. Basically, the thicker the nacre, the more brilliant the pearl´s luster, and the higher the cost of the Tahitian pearls.
Size – Similar to all types of precious stones, the larger the pearl, the more valued it is. Tahitian black pearls tend to be larger than most other types of pearls, ranging from about 7.5mm to 14mm. The size of Tahitian pearls is measured to the half millimeter, and the price difference goes up rapidly for every increase of 0.5mm. Tahitian black pearls can be found as big as 16mm to 18mm, although these are quite rare and very expensive.
Shape – When people think of the shape of a pearl, they tend to think of a perfect sphere. This is a large misconception, because only the best and most expensive pearls are close to a perfect sphere. The shape of pearls are broken down into a few categories: round, semi-round, semi-baroque, baroque, and ringed of circled. The shape of the pearls on Tahitian black necklaces are usually round or semi-round, because they look the best on a necklace.