Basically, pearls like diamonds are one of the most sought after jewellery in the world. Diamonds are for rings and pearls are for necklaces. And like diamonds, pearls can also be one of the most expensive. However, there are a lot of criteria that determines the exact prices of specific pearls.
Basically, there are four types of pearls based on their origin or on how they are grown. One of the most affordable among the seawater pearls are the Akoya pearls. Akoya pearls are considered the classic pearls, they have been produced and sold for over 100 years. Before, these pearls were very expensive but in the 20th century, prices have dropped probably due to mass production, specifically in Japan and China. These pearls are the smallest in the pearl-variety, they range from 1mm to 10mm (extremely rare). They have perfectly round shapes and they are naturally neutral in color without colourful overtones compared to the other varieties which usually have the pink, green or blue overtones. Rare Akoyas sometimes produce pearls with blue overtones and black Akoya pearls have been exposed to Cobalt-60 radiation treatment because there are no black Akoya pearls.
Next, are the freshwater pearls, they are also at the low-price variety. From the name, they are farmed and cultured in freshwater, mostly in China, the lakes and riverbeds in Japan and the United States. They are extremely mass-produced, but unlike the Akoya each freshwater pearl is unique. It is rare to find perfectly round pearls in the freshwater variety and they are likely to be more expensive. They also vary in color, they come in a long range of natural pastel colors, and size, ranging from 1mm diameter to 15 mm. They are sorted according to these characteristics in addition to their texture and luster.
Now, to the more expensive variety starting with the Tahitian pearls. These pearls are made by Black-lip pearl oysters. They are mostly cultured in French Polynesia, the Cook Islands, and the Micronesian Islands. These pearls have the most exotic color range, from creamy whites to greys to regal greens, to iridescent peacock and to deep blacks. The most sought after are the black ones with the peacock green overtones. Unlike the akoya which is also a saltwater pearl, their nacre is thicker – which accounts for the increase in price. The grading for Tahitian pearls are under the Polynesian government and they have high standards, so you can expect that these pearls are of very good quality. Their sizes range from 8mm to 18mm, they are smaller than the South Sea pearls but they have a more variety of color. Also, they are almost always round in shape and they have more value that way. They are within the price range of probably $50 to $5000 or more.
The most expensive among the pearls are the South Sea pearls. They are large and the most lustrous among all the other pearls. South Sea pearls are obviously produced in the South Seas, specifically in the Philippines and Indonesia and a little from Australia. It takes 2 to 4 years to grow them which will probably be how long you will be saving up to afford these beautiful and natural gem. Their colors vary from creamy white to deep golds and considering that they stay in the oyster for 2 to 4 years, they grow larger than any other type of pearl ranging from 10mm to 13mm and they have very thick nacre, meaning they shine and glow the most. However, due to their sizes, unlike the other saltwater pearls they do not have perfectly round shapes. Due to their natural beauty and luster combined with their rarity, they have a very high value. A string of South Sea pearls of good quality could cost you at least $100, 000.
Basically, there are two criteria to evaluating a pearl: one is luster or nacre and two is roundness. 70% of the criteria should be given to luster and 30% to roundness. Luster results from the nacre that forms around the pearl while it is still with the oyster. Luster does not only refer to the level of shine of the pearl but also the degree of glow it reflects from a light source. It also signifies the durability of the pearl, the lustrous the pearl is the more nacre layers it has. Hence, your pearl would last longer and would not be easily chipped or peeled. The roundness or the shape of the pearl also varies and perfectly round shapes are very rare therefore they are also very valuable. The color of the pearl also matters although it doesn’t have much effect on the price but it matters on a person’s preference or taste. Lastly, on a jewellery, specifically a necklace, it is also important to look at how the pearls match to each other especially in a string of pearls. You need to check whether they are uniform in color, size and luster to be able show that overall beauty.