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Perfect shining spheres. Lustrous baroque forms. Seductive strands, warm to the touch. Pearls are simply and purely organic.

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Beautiful Luster

Pearl’s special luster sets it apart from other gems.

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Perfect Sphere

Perfectly spherical pearls of excellent quality are extreme rarities.

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Smooth as Silk

Few pearls are completely blemish free.

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About Pearl

about pearl

Perhaps the best-loved gems of all time, pearls—natural and cultured—occur in a wide variety of colors. The most familiar are white and cream, but the palette of colors extends to every hue. Natural pearls form around a microscopic irritant in the bodies of certain mollusks. Cultured pearls are the result of the deliberate insertion of a bead or piece of tissue that the mollusk coats with nacre.

Pearl Description

Pearl History and Lore

Pearl Journey

Birthstones & Anniversaries

Pearl is the birthstone for June and the gem of the third and thirtieth anniversaries.

2206 BC

A Chinese historian writes about pearls for the first time.

653 Fifth Avenue

In 1917, Pierre Cartier traded a double strand of natural pearls for a mansion on Fifth Avenue in New York City.


Kokichi Mikimoto successfully cultures a pearl in Japan.


  • Mineral: Calcium Carbonate
  • Chemistry: CaCO3
  • Color: White, black, gray, yellow, orange, pink, lavender, green, blue
  • Refractive Index: 1.52-1.69
  • Specific Gravity: 2.60-2.85
  • Mohs Hardness: 2.5-3.0


There are a number of processes used to alter the color, apparent clarity, or improve the durability of gems.

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Some gemstones have synthetic counterparts that have essentially the same chemical, physical, and optical properties, but are grown by man in a laboratory.

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Any gem can be imitated—sometimes by manmade materials or by natural materials chosen by man to impersonate a particular gem.

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gem love

Why We Love This Gemstone


Luster results from reflection of light rays off the pearl’s surface, and from concentric inner layers of nacre, like light bouncing off a convex mirror.


Natural or cultured, saltwater or freshwater, nacreous or not, pearls come in a myriad of shapes and colors, telling the stories of the mollusks in which they grew.


Pearls reflect the condition of the dynamic environments in which they grow. The quality of a mollusk’s surroundings is inextricably linked to its health and the quality of its pearls.

Quality Factors

An assessment of the following characteristics determines the value of each type of pearl.


quality factors

Pearls with high luster have sharp bright reflections on the surface.

Surface quality

quality factors

The number of blemishes on a pearl's surface is evaluated to judge quality.


quality factors

Spherical pearls are the most valued but symmetrical drops are also sought.


quality factors

Although white is most classic, appreciation has grown for more unusual natural colors.

Nacre thickness

quality factors

Nacre thickness is evaluated to make sure that cultured pearls are durable as well as beautiful.


quality factors

Cultured pearls range from 2-16mm in diameter, depending on the mollusk used.


quality factors

For pearl strands and multi-pearl pieces, how well the pearls match (or mix) affects the value.

Pearl Quality Factors: The Comprehensive Guide


Explore sources, gemological research, and the role of gems in history.

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Strong Pinkish Purple Freshwater Bead-Cultured Pearls

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 Large open mussel shell with pink interior

Freshwater Pearling in Tennessee

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Pearl farm on the Indonesian island of Lombok

Bead-Cultured and Non-Bead-Cultured Pearls from Lombok, Indonesia

Nicholas Sturman, Jeffery Bergman, Julie Poli, Artitaya Homkrajae, Areeya Manustrong, and Nanthaporn Somsa-ard , Nov 7, 2016 Read Article
Culturing Pearls in Mergui, Myanmar

GIA Field Gemologists Visit Pearl Farms Near Mergui, Myanmar

GIA Staff , Sep 18, 2015 Read Article