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Azure sky, robin’s egg blue: Vivid shades of turquoise define the color that’s named after this gem.

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This turquoise is cut in a cabochon: the most common shape.

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Robin’s egg

The preferred color for turquoise is a pure sky blue.

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Some buyers prefer the presence of matrix in fashioned turquoise.

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Turquoise is an aggregate of microscopic crystals that form a solid mass.

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The intense blue color in this rough is due to the presence of copper.

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Veins of matrix in this turquoise are remnants of its surrounding rock.

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About Turquoise

About Turquoise
Turquoise is found in only a few places on earth: dry and barren regions where acidic, copper-rich groundwater seeps downward and reacts with minerals that contain phosphorus and aluminum. The result of this sedimentary process is a porous, semitranslucent to opaque compound of hydrated copper and aluminum phosphate.

Turquoise Description

Turquoise History and Lore

Birthstones & Anniversaries

Turquoise is the traditional birthstone for the month of December and the gem of the 11th anniversary.

4,000 BC

Turquoise buried in Ancient Egyptian tombs is among the world’s oldest jewelry.


Ancient Egyptians called turquoise “mefkat,” which also means “joy” and “delight.”


Montezuma, thinking Cortes was Quetzalcoatl, gave him the god’s favorite gem: turquoise.


  • Mineral: Turquoise
  • Chemistry: CuAl6(PO4)4 ·(OH)8 ·5H2O
  • Color: Blue to green
  • Refractive Index: 1.610 to 1.650
  • Birefringence: Not detectable
  • Specific Gravity: 2.76 (+0.14, -0.36)
  • Mohs Hardness: 5 to 6


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


The spiderweb of veins that appear in turquoise are matrix: evidence of the surrounding rock.


A legacy of turquoise appreciation spans the globe, from ancient Egypt to Mesoamerica to China.


Turquoise is colored by copper, which creates some of the most vivid blues and greens in gems.

Quality Factors

Turquoise is judged on its color, texture, and the absence of matrix.


quality factors

The even blue color of this cabochon would be called Persian blue in the trade.


quality factors

These free-form turquoise cabochons show a typical matrix pattern.


quality factors

Although turquoise is usually cut into beads and cabochons, it can also be carved.

Carat Weight

quality factors

Cutters work around large areas of matrix to yield pieces of evenly colored turquoise. 

Turquoise Quality Factors: The Comprehensive Guide


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

Turquoise from Zhushan County, Hubei Province, China

Turquoise from Zhushan County, Hubei Province, China

Quanli Chen, Zuowei Yin, Lijian Qi, and Yan Xiong , Oct 24, 2012 Read Article
Turquoise bead with artificial metallic pyrite.

Turquoise with Simulated Matrix

Rebecca Tsang , Jan 27, 2017 Read Article
IMG-FA13-LN 154336 300x169

Turquoise with Fingerprint Pattern

Tara Allen and Amy Cooper , Oct 17, 2013 Read Article
Recent production of turquoise from Polk County, Arkansas

Turquoise from Western Arkansas

Jennifer-Lynn Archuleta and Nathan Renfro , May 11, 2018 Read Article