Pearl Quality

Published On: 
January 13, 2020

The 5XS System

Pearls are one of the oldest and most cherished gemstones. They are organic and come from the oceans. As such they have intrigued man-kind since the beginning of civilizations. Even today, people rarely understand pearls. In this page you will learn about our 5XS grading system. Due to the complexity of pearls, something like the Diamond’s 4 C’s is not enough. Therefore, we came up with the following system:

  • Shine
  • Size
  • Shape
  • Surface
  • Shades
  • Selecting the best pearl



The most important factor in determining a pearl’s value is its shine. Shine (also known as luster) refers to the surface property that imbues cultured pearls with their beauty and ability to break and reflect light. When checking pearls for luster, view them while standing with your back to a source of light. The sharper your reflection on the surface of the pearl, the higher is the luster and the better the quality. With pearls, everything is a matter of personal taste, however shine is the one quality that everyone wants more of. Luster is a great indicator of the quality and thickness of the pearl’s Nacre

Grading pearls by luster



Size is a very important determinant of price. Pearl size is determined by the size of the implanted nucleus and the thickness of the nacre that grows layer by layer around the nucleus. A large cultured pearl is of little value if it lacks nacre thickness: whereas a thinly coated pearl will crack and discolor, one with a thick nacre coating will last a lifetime if properly cared for.

Grading pearls by size



Perfectly round cultured pearls are the most rare. Although most cultured pearls are nearly round, only about 1% are perfectly spherical. To check a strand for roundness, roll it across a flat surface. The strand should move evenly and smoothly. Among other shapes one may find: button shapes, oval, drops, triangle and baroque or Keshi which are irregular “random” shapes (Keshi pearls have no nucleus). While perfectly round shapes are the most expensive, it does not mean they are the best. As with everything else, it is ultimately a matter of personal preference. Some may prefer the randomness of the Baroque pearl to the perfection of the round pearl.

Grading pearls by shape



As with any product of nature, all cultured pearls have minor imperfections. A high quality cultured pearl is smooth and free of large pits, blemishes or discolorations. When pearls come with a thick coating (nacre, or “Maki” in Japanese), they tend to have a more uniform color and high luster (compared to blemishes, this is harder for an untrained eye to notice). In addition to these blemishes, the trained eye will also notice the smoothness of the nacre. Professional wholesalers call this “Orange Skin” or “Shark Skin” representing nacre that is a bit coarse, resembling orange skin. 

Grading pearls by surface cleanliness



Pearls come in a large variety of color shades. The major color classifications are white, pink, silver, cream, gold and black. Cultured pearls also have a secondary color or “overtone” usually rose, green or blue – around the surface of the pearl. These overtones exist in pearls with thick coating. No matter the shade you select to complement your skin tone, the color should appear to emanate from deep within the pearl. If selecting a strand or earrings, the pearls should be consistent in color (unless the strand is classified as a multicolor strand which has mixed colors by definition).

Black tahitian pearl multicolor necklace AAA luster and fancy colors
A great example of the different shades and overtones of Tahitian pearls.

Selecting the Best Pearl


When people visit our showroom in Tokyo, we are often asked “which is the best pearl?”. It is important to remember that there is no such thing. Granted, there are rarer pearls, reflected by their price, however these may not be to your liking. Pearls are unique and diverse. So the real question should be: “Which is the best pearl for me?”.

The answer to that question is the balance between your personal preference, your skin tone, what you usually wear and of course your character. As we helped many customers select the right pearls for them, we are very experienced in the art of matching pearls to skin tones. Please contact us and set an appointment with one of our pear experts who will gladly help you choose the right pearl for you.

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