Quahog Pearl

saf-ahyuh r
June Birthstone

Among America's rarest and most stunning pearls, quahog pearls were first valued by Native Americans along the coast of New England. This non-nacreous calcareous concretion forms in colors from white to brown, to purple and lilac in round, button and teardrop shapes. Such pearls are typically collected by fishermen as a result of harvesting the meat of the shellfish.

Quahog Pearl Polished
Quahog Pearl Classification
Common Name Quahog Pearl
Species Pearl
Quahog Pearl Optical Properties
Transparency Translucent - Opaque
Refractive Index 1.530-1.685
Birefringence 0.155
Optic Character NA
Optic Sign NA
Polariscope Reaction Aggregate (AGG)
Pleochroism None
Quahog Pearl Characteristic Physical Properties
Hardness 2.5-4.5
Specific Gravity 2.610-2.850
Toughness Good
Inclusions Quahog pearls are non-nacreous with fibrous structure. They have a color banding that sometimes creates an "eye" effect.
Luster Dull, Vitreous
Stability Poor
Fracture Uneven
Cleavage None
Quahog Pearl Chemistry & Crystallography
Chemical Name calcium carbonate + conchiolin and water
Chemical Formula CaCO3 with H2O and other organic materials
Crystal System NA
Chemistry Classification Organic

Quahog Pearl Colors

  • Black Quahog Pearl Black
  • Yellow Quahog Pearl Yellow
  • Purple Quahog Pearl Purple
  • White Quahog Pearl White
  • Brown Quahog Pearl Brown

Alternate Names

Cohog And Quohog

Countries of Origin

United States of America (the)


Avoid cosmetics, perfumes, hairsprays, heat and household chemicals.

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Tim Matthews


Tim Matthews

Tim Matthews is President and Chief Executive Officer of Jewelry Television® (JTV), as well as a member of the company's Board of Directors. He oversees and leads all aspects of the company's powerful omni-digital retail platform that uniquely specializes in fine jewelry and gemstones. His passion for business and gemstones has led him to become a recognized expert in the field of gemology. He is a life member of the Gemmological Association of Great Britain (Gem-A) and has earned Gem-A's highest degrees, the Gemmology (FGA) and Diamond (DGA) diplomas. He is also a Graduate Gemologist (GG) of the Gemological Institute of America (GIA) and has also completed GIA's Graduate Diplomas in Diamonds, Colored Stones and Pearls. Under his leadership, JTV has become the leader in the sourcing and selling of color gemstones and jewelry.

This page was created on June 27, 2014.

This page was last edited on October 24, 2019.