What color is the most expensive pearl?
Pearl is the only precious stone of bio-organic origin. Pearls are formed inside sea shells, which layer by layer cover a random grain of sand with nacre.
Everyone knows pearls of milky white color, as well as black pearls, which are diametrically opposite to them, but what kind of pearls are there in other colors?
- Types of pearls
- Types of sea pearls
- Freshwater pearls and their types
- Classification of pearls by quality
Types of pearls
The color of a pearl is determined by many factors in the formation of the stone. The shape, shade, and size of the pearl are determined gradually, throughout the entire period of formation of the stone, and in natural conditions this often takes years.
The qualities of future jewelry are influenced by:
- the variety of shellfish in which it grows;
- water temperature and composition;
- the presence of a current in the place of growth.
Pearls can grow in fresh or sea water, which significantly affects its appearance and cost.
Types of sea pearls
At the moment, the extraction of pearls from the depths of the ocean, in wild shellfish, is not very common. The widespread practice of harvesting pearls in this barbaric manner in past centuries affected the biodiversity of the ocean, as up to a ton of shells were required to obtain a few pearls.
Nowadays, pearls are mined on cultivated plantations, where the quantity and quality of the future stone can be controlled and branded varieties can be grown in large quantities.
What color are pearls?
The most common is white pearls. The first plantation that cultivated it used oysters called acoya, which gave the variety its name. Akoya pearls are now grown in China, Japan and Vietnam. These are light varieties of pearls, pure white or colored in various shades of silver, pink, and champagne. The most valuable shade of this variety is pearl with a green or pink tint and bright shine.- Tahitian pearls, on the other hand, are distinguished by a variety of dark shades. Among this variety you can find black pearls with various shades, as well as blue, brown and gray pearls. The most expensive stone among the dark range is green pearls, or rather dark ones with a green metallic tint. Regarding this variety, it should be noted that Tahitian pearls are not grown on the island itself. Tahiti is the name of a center engaged in the cultivation of oysters and the sale of pearls.
- South Sea pearls are the collective name for light-colored pearls that are grown in a large breed of mollusk. This pearl is very expensive because of its special structure – it has the thickest layer of nacre, unlike other varieties. Due to this, the pearl has a matte silk shine that you will not find in any other variety. This variety includes gold pearls, white pearls with a silver tint, and champagne beige pearls.
The Cortez variety is grown off the coast of Mexico. This is also a fairly expensive dark variety (but not as dark as Tahitian pearls – natural black pearls grow only there). The types of pearls grown in this variety are colored pearls in golden, graphite, brown and silver shades. These pearls are distinguished by their rich iridescence, reminiscent of a puddle of gasoline.
All of the above varieties of pearls grow in seawater and are distinguished by their large size and strong shine caused by aggressive salt water.
Freshwater pearls and their types
But there are also plantations of freshwater pearls, distinguished by their unique colors and shades. Freshwater pearls are typically less expensive due to their irregular shape, subdued matte shine, and high harvest volumes. Varieties of freshwater pearls:
Kasumi pearls are a type of pearl grown in Japan at Lake Kasumi-ga-ura. It has a thick layer of mother-of-pearl, but very rarely forms round beads and a smooth surface. However, the iridescence of its colors makes these colored pearls extremely popular among jewelry designers who can play with the unique shape of the pearl in their products. Kasumi pearls come in a variety of colors from white to deep black. Among this variety you can see pink pearls, lavender, lilac, green pearls and all sorts of iridescent shade combinations.- Keshi is also a Japanese type of pearl that consists entirely of mother-of-pearl and has no core. Previously, such pearls were considered “defective” because of their flat concave shape, reminiscent of a plucked petal, but now, thanks to their beautiful shine and noble iridescence, these pearls are used to make various jewelry compositions, buttons, etc. These pearls come in both light and dark shades, and the most popular are their lavender and pistachio color variations.
Biwa is another type of irregularly shaped pearl that is also mined in Japan. Biwa pearls do not have a core, which is why they form peculiar stalactites of pure mother-of-pearl. The color variations are endless – pink pearl, gold, beige, blue pearl, green and graphite – any shade can be found among these unique pearls.
Classification of pearls by quality
In addition to individual aesthetic preferences, such as the color of pearls, there are also formal jewelry criteria for evaluating pearls. So, which pearls are considered the most valuable? There are several criteria for evaluating pearls:
Pearl color. As already mentioned, depending on the breed of mollusk and growing conditions, the color of the pearl may change. When assessing the color of a stone, attention is paid to the purity of the color, the uniformity of the color of the pearl, and the play of shades. In addition, dark colored pearls, especially those with a blue or green tint, are valued slightly higher than others.- The shine of a pearl. Simply put, the brighter a pearl shines, the higher its value. For a detailed assessment of an individual stone, various studies can be carried out to reveal the exact thickness of the mother-of-pearl layer.
- Ideal spherical shape. In addition to the ball, pearls can form all sorts of geometric shapes – a drop, a hemisphere, a rice shape, buttons, etc. However, one should not forget that the criterion of value affects only the cost of the stone; in fact, jewelers can create delightfully executed expensive compositions from “wrong” stones.
- Surface smoothness. This indicator applies only to pearls of spherical color and demonstrates the absence of defects, purity and radiance of the top layer of the pearl.
Size. Everything is simple here: the larger the pearls, the more expensive they are. In jewelry, the most expensive pearls reach sizes of 1,5-2 cm in diameter. History knows cases of discovering truly gigantic pearl samples – the most famous example is the Pearl of Allah, which weighs more than 7 kg.
The formal designations for pearl grades are AAA-A and AD. These are different classifications, the highest grade being AAA and the lowest being D.
Pearls whose class uses letters other than A are considered unsuitable for jewelry making and are not used in jewelry.
The highest class is assigned to pearls that are practically free of surface defects, have a pure color, an even beautiful shine and a regular shape. There are very few such stones. The lower stages of the classification are occupied by pearls with any defects, but if defects occupy more than a quarter of the stone, then it is not allowed to enter the jewelry machine.
1.1 Pearl color: natural and refined
Many buyers and craftsmen are faced with the question of how to distinguish the natural color of pearls from refined ones. High quality dyed pearls can be just as beautiful while being more affordable.
There are main points worth paying attention to:
Price — Most types of natural-colored pearls tend to command a high price. If the price is very low, the pearls are most likely colored.
Size – if the pearl size is less than 9mm and it is labeled as a Tahitian or Golden South Sea pearl, it is unlikely to be the true color, Akoya pearls, on the other hand, produce a wide range of pearls up to 9mm.
Hole — carefully inspect the drilled hole of the pearl. If the core looks dark and the nacre inside looks white, then the pearl is colored. Another thing that indicates a dyed pearl is dye concentrated around a hole or somewhere else on the pearl’s surface.
Color — Artificial color can be determined under a microscope; the color will be distributed unevenly, in spots.
Other things to note: If the pearl has been artificially treated, there will be a dye present or a darkened core (if irradiation was used). Also, compared to natural-colored cultured pearls, dyed pearls are softer.
Despite this, treated pearls are natural.
1.2. What is the color of a pearl made of?
Pearl color plays a crucial role in the evaluation of a single pearl – it includes the base color (pigment), overtones and luster (shimmer). Each pearl develops individually, so pearls come in a variety of colors, from white to black.
Primary color (pigment) – natural pearl color. It is the result of a combination of factors – the type of oyster, water conditions and (in the case of cultured pearls) the type of nucleus implanted in the pearl. Can be white, silver, cream, gold, green, blue or black.
rice. Basic pearl colors
Overtones – additional translucent colors that appear on top of the main color of the pearl in sunlight, while the main color remains dominant, and the overtones only slightly change it. It happens that one pearl has several overtones at once or that there is none; overtones also come in different intensities.
rice. Overtones of white freshwater pearl
rice. Overtones of golden pearls
Chandelier (glimmer)– the luster of the mother-of-pearl layer, it is determined by the light reflected in various thin layers of mother-of-pearl and changes at different angles (since all pearls have a different amount of nacre and layers)
When choosing a pearl, you need to take into account its color, tone and shade saturation. The intensity of the color also affects the value of the pearl.
2. How pearls are colored. What dyes are used.
The most common method of coloring pearls is infiltration (impregnation of pearls with some substance), the pearls are bleached and then painted with dyes. Freshwater pearls are easy to dye in a short time (a few hours or days), because. its layer of mother-of-pearl is softer. South Sea pearls take much longer (one to two months) and dyeing such pearls is very expensive. Due to the thin layer of nacre, it requires bright light to speed up the penetration and even distribution of the dye (this method is called “laser dye”).
rice. Dyed pearls
Pearl processing consists of several steps (which we will cover in the next article) and some of them involve dyeing the pearls.
— Preliminary processing. Most pearls (both saltwater and freshwater) are pre-bleached to lighten any uneven dark areas that may appear underneath the nacre. The result is long lasting, providing a more uniform appearance and preparing the pearls for the next steps.
— Coloring. After polishing and grinding the pearls, when the master makes sure that there are no defects, they begin to color the pearls. Dyes can be organic (aniline dyes) or inorganic (potassium permanganate). For example, to obtain a rich brown color, a mixture of cobalt salt and alkali is used, after which it is irradiated with ultraviolet light; To give it a pink color, pearls are dipped in a diluted oil or alcohol solution mixed with red paint. To darken pearls, a solution of silver nitrate was previously used, which was dissolved in a dilute ammonium solution for two to three days, after which the pearls were exposed to sunlight; now, as a rule, gamma irradiation is used for darkening.
— Irradiation. If the pearls need to be darkened, as irradiation is used correctly, the gamma rays darken the core and this results in a dark colored pearl (dark enough to resemble the natural color of black South Sea pearls, at a more affordable price). Irradiation also enhances the luster of the nacre layer in some pearls. At the same time, pearls do not retain radioactivity, so this processing method is safe. Most experts say that the effect of such treatment is permanent.
2.1. Creative coloring methods
There are more creative ways to dye pearls – you can dye not only them, but also the seeds that are used to grow cultured pearls. Some craftsmen like to paint pearls in sections, creating fancy designs on it – for this, a channel is created, which is drilled into the pearl, the paint fills the channel and a separate area is painted.
