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The essence of the color purple, amethyst is beautiful enough for crown jewels yet affordable enough for class rings.

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Royal Purple

This 13.44-ct. Zambian gem displays the rich royal purple color typical of fine amethysts.

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Antique Cut

Amethyst is available in many shapes and sizes including antique cuts.

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Eye Clean

The finest amethysts are typically eye-clean.

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Six Sided

These crystals are typical six-sided columns with tapering faces that meet in a point.

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Amethyst crystals often show purple and colorless zones.

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Distinctive Markings

Like many quartz varieties, amethyst might form radiating crystal clusters

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About Amethyst

About Amethyst

Amethyst was as expensive as ruby and emerald until the 19th Century, when Brazil’s large deposits were discovered. It was believed to prevent intoxication—amethystos means “not drunk” in ancient Greek. Today, as the most valued quartz variety, amethyst is in demand for designer pieces and mass-market jewelry alike, and its purple to pastel hues retain wide consumer appeal.

Amethyst Description

Amethyst History and Lore

Birthstones & Anniversaries

Amethyst is the birthstone for February and the gem for the 6th and 17th wedding anniversaries.

St. Valentine

The patron of romantic love wore an amethyst ring carved with the image of Cupid.

Camillo Leonardi

The astrologer wrote that amethyst quickens intelligence and gets rid of evil thoughts.

164 Pounds

Single amethyst crystals can be huge: the GIA Museum displayed a doubly terminated crystal that weighed 164 pounds.


  • Mineral: Quartz
  • Chemistry: SiO2
  • Color: Purple
  • Refractive Index: 1.544 to 1.553
  • Birefringence: 0.009
  • Specific Gravity: 2.66
  • Mohs Hardness: 7


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


In gem localities like Brazil, amethyst sometimes forms in hollow, crystal-lined geodes so big you can stand in them.


Even fine amethyst has a modest price tag. Large gems remain affordable as price per carat does not rise dramatically with larger size.


In Bolivia, amethyst and citrine occur in the same crystal. The unique gems, called ametrine, are half purple and half yellow.

Quality Factors

Assessment of the following characteristics determines amethyst’s value.


quality factors

The finest amethyst color is strong reddish purple to purple with no visible color zoning.


quality factors

Most amethyst doesn’t have inclusions you can see without magnification.


quality factors

Amethyst is cut into a variety of standard calibrated shapes, including rounds and ovals.

Carat Weight

quality factors

Amethyst is available in all size ranges for setting into a variety of jewelry styles.

Amethyst Quality Factors: The Comprehensive Guide


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

Four trapiche-like amethyst cabochons.

Trapiche-like Amethyst from Brazil

Ziyin Sun, Jonathan Muyal, and Dylan Hand , Aug 9, 2018 Read Article
Color zoning in amethyst from Boudi, Morocco

Amethyst from Boudi, Morocco

Fabrizio Troilo, Abdelghani El Harfi, Salahaddine Mouaddib, Erica Bittarello, and Emanuele Costa , Apr 30, 2015 Read Article
Amethyst crystals from Morocco

Moroccan Amethyst:
Mining and Marketing

Andrew Lucas and Tao Hsu , May 8, 2017 Read Article
Amethyst with a large aqueous primary fluid inclusion

Large Aqueous Primary Fluid Inclusion in Amethyst

Ziyin Sun and Jonathan Muyal , Nov 7, 2016 Read Article