Learn About Pearl Qualities, Sizes & Markings

Qualities

Saltwater and freshwater pearls come in shades of white, gray and black. Shapes range from perfectly round to oblong. The most expensive pearls approach perfect symmetry. Pearls with no definable shape are called baroque. While less costly, baroque pearls can be extremely beautiful. Apart from size, the most important quality in a pearl is luster - the deep-seated glow that distinguishes the pearl from other gems.

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Sizes

Cultured pearls are sized in millimeters (25.4 mm equal one inch). Round pearls are measured by their diameter; oblong pearls are measured end to end.

The size of the pearl greatly depends on the type of pearl. Freshwater pearls range in size from about 3–7mm, Akoya pearls range from about 6–8.5mm, and South Sea and Tahitian pearls can reach sizes as large as 13mm.

Pearl Size Chart In Millimeters
5-5½ mm	6-6½ mm	7-7½ mm	7½-8 mm	8-8½ mm	9-9½ mm	13 mm

Surface Markings

As an oyster creates a pearl, the layers of nacre do not always adhere smoothly. Sometimes spots and bubbles can appear in the layering process. Pearls with the smoothest surfaces are the highest-quality, most sought-after pearls. At Jewelry By Net, to offer you a range of prices, we offer pearls with a range of surface qualities.

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