Quality of a Pearl

Pearl Amor considers six physical factors in determining the quality, beauty, and value of a pearl: Luster, Nacre Thickness, Surface Perfection, Color, Shape, and Size.

Luster

Grade AAA (Very good)                     Grade AA  (Good)                           Grade A (Middle)

     

If only one factor were to determine the worth of a pearl, luster would be the top consideration. As an expression of a pearl beauty, luster is determined by the amount of light reflected from the pearl surface as a combination of its outer brilliance and deep inner glow. The highest quality pearls with the best luster will reflect a clear mirror image of the objects around it, and will also have a distinct sharp contrast between the pearl bright and shaded areas. This actually creates the illusion of a glowing ball within a pearl.

The thickness and quality of a pearl nacre affects its overall luster. However, a thick nacre coating does not always guarantee that a pearl will have a high luster. Genetic imperfections in some oysters inhibit them from secreting nacre in perfect patterns that result in high luster. Generally, avoid any pearls that appear too white, dull, or chalky as you can be sure these are lower value pearls. Remember to examine the luster of pearls under a fluorescent lamp and in front of a light colored or optimally white background.

Typically having the thickest nacre coating, the South Sea Pearl exudes an exceptionally deep and rich luster set apart from that of other types of pearls. Although referred to as more satiny than mirror-like when compared to the Akoya Pearl, the luster of the South Sea Pearl is exceptionally beautiful as it possesses a soft iridescence.

Nacre Thickness

Pearl nacre is the natural coating a mollusk produces to protect itself from irritants such as shell fragments or in the case of a cultured pearl, an implanted bead nucleus. A pearl nacre is created by thousands upon thousands of layers of this crystalline substance technically known as calcium carbonate (CaCO3). This same radiant iridescent material is what lines the inner surface of oyster shells and is referred to as Mother of Pearl.

Nacre thickness is a very important factor in determining pearl quality in that it directly affects the durability and therefore, how long the beauty of a pearl lasts. Along with nacre thickness, nacre quality is further determined by how light reflects through the layers of the nacre and illuminates a pearl. Sometimes pearls with thick nacre fail to exhibit the intensity of luster that is expected due to the way in which the layers of the nacre crystallized. Oftentimes this has to do with environmental factors such as water temperature and stability of overall water conditions, which affect the speed at which the nacre is produced.

A few quick ways to evaluate nacre thickness is to look for uniform iridescence, intensity of luster, and cracks and peeling. Estimate thickness by observing the nacre at the drill hole. The most accurate way to determine nacre thickness is through x-ray done at a gem testing laboratory.

For Akoya Pearls, a minimum nacre thickness of 0.4mm is recommended to ensure that the pearls will last a lifetime. For South Sea Pearls and Tahitians, which typically have thicker nacre, a minimum of 0.8mm is recommended. In several countries where these pearls are cultured governments have imposed a minimum nacre thickness of 0.8mm to prohibit low quality pearls from being exported.

Surface Perfection

Grade AAA (Clean)                             Grade AA (Little Flaw)                          Grade A (Middle)

Considered by experts as the second most important factor in pearl evaluation, surface perfection refers to blemishes that appear on the pearl and ranges from lean?to eavily blemished.?Imperfections can appear as blisters, pimples, spots, cracks, indentations, welts, bumps, and dark spots. As a product of nature, pearls are almost never flawless and small blemishes are common. But of course, when considering value, the cleaner the surface of the pearl, the more valuable it is.

When examining pearls for imperfections, contrary to using a light colored background that is typically best for comparing most pearl characteristics, use a black background to reveal small detail blemishes. Also, while holding a pearl out in front of you at eye level, examine it in both diffused and intense light.

To be considered lean,?the pearl must have no detectable spots, bumps, cracks, circles, wrinkles, or any other type of blemish. On the other hand, a eavily blemished?pearl has many pronounced flaws. It is important to note the difference between damaging and non-damaging blemishes. A damaging blemish such as a crack worsens over time, while a non-damaging blemish such as a bump or spot remains the same over time. Damaging blemishes are obviously worse.

As a business philosophy, at Pearl Amor, we continue to focus on pearl beauty. We put every effort into acquiring only the cleanest and most sought after pearls and making them available to our customers. We believe this keeps things lean?and simple.

Color

Pearls are available in a fascinating array of colors from white to black and virtually every color in between. The choice of pearl color is important to consider based on preferences and cost, as well as the wearer skin, eye and hair color. When evaluating pearl color, it is important to note both body color and overtone. The body color refers to the basic color, while the overtone refers to the presence of a secondary color, also known as a int.?For example, pearl with a white body color can posses a surface iridescence reflecting a cream overtone. Although pearl color choice is a personal preference, rose and white overtones are commonly preferred by women with fair skin, while cream and gold tone pearls are most flattering to those with darker complexions.

In addition to basic color, a pearl color tone intensity is also evaluated. Darker toned pearls that are richer in color are highly desirable and costly when compared to lighter intensity color pearls.

Shape

  Perfect Round                                         Drop                                               Button

Very few pearls actually come out of an oyster perfectly round, which is why such pearls are the most rare and valuable. With many shapes available, pearls are first divided into three shape categories: symmetrical, spherical, and baroque. Within these categories, they are further defined by unique shapes such as teardrop, button, pear-shape, coin, flat, rice, oval, and cross just to name a few. Spherical pearls are by far considered the highest quality, although symmetrical pearls including pear and teardrop shape, along with baroque pearls are gaining more popularity due to their unique shapes and lower costs.

Size

The size of a pearl is measured across its diameter and its range can be smaller than 1mm to as large as 20mm or more. Not as an indicator of quality but rather the value of the pearl, size affects a pearl price. The reason why larger pearls cost more is very simple in that it takes more time and risk to cultivate a larger size quality pearl. Sizes vary depending upon the type of pearl: freshwater pearls typically range in size from 3 to 8mm, Akoya Pearls range from 3.5 to 10mm, and South Sea Pearls including Tahitians Pearls range from 10 to 18mm. The average and most popular pearl size sold today is 7 to 7.5mm, a good balance between size and cost.


Qifu Jewelry Grading System

To simplify and best represent the standard factors of pearl grading (luster, nacre thickness, surface perfection, color, shape, size), the Pearl Amor grading system accurately and consistently categorizes these 6 important factors by three individual grade labels. Along with the three major categories (AAA, AA, A) there are also two sub grades (AA+, A+), wherein the + represets a slightly less blemished surface.

AAA Pearl Grade

  Luster :High/Intense with an exceptional mirror-like quality

  Nacre Thickness :Very thick, with a minimum of 0.5mm thickness for Akoya Pearls

  Surface Perfection ?Clean and virtually flawless

  Color :Varied colors with sharp and distinct overtones

  Shape ?Perfectly round

  Size :Varied

AA Pearl Grade

  Luster :High with a clear reflection

  Nacre Thickness :Thick, with a minimum of 0.4mm thickness for Akoya Pearls

  Surface: Perfection ?Slightly blemished with minimum 90% clean surface

  Color :Varied colors with good overtones

  Shape :?Round

  Size :Varied

A Pearl Grade

  Luster :Medium with a slightly dull reflection

  Nacre Thickness :Medium to thin with a nacre thickness 0.3mm or less

  Surface Perfection :Blemished with minimum 75% clean surface

  Color :Varied colors with minimal to no overtone

  Shape ?Near round to off round

  Size :Varied