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Ametrine

This transparent quartz has colors of both amethyst and citrine, and is called ametrine or amethyst-citrine.

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Golden Yellow

Golden shades of citrine glow in the heart of this gem.

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Lovely Purple

Shades of amethyst’s purple contrast with citrine’s orangy yellow.

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Blended shades

Reflections from the back facets blend into sunset colors in this rectangular cut.

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Bicolor

This quartz crystal shows both amethyst and citrine colors.

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Top Quality

This facet grade rough piece will produce a superb cut gem.

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Rare

With only one producing source, the supply of ametrine is very limited.

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Overview

About Ametrine

Whether projecting from pegmatite walls or encrusting cavities in volcanic rock, quartz abounds worldwide. People have used quartz in jewelry for thousands of years. When quartz displays the colors of amethyst and citrine in a single gem, the material is called ametrine or amethyst-citrine. Ametrine’s only commercial source is the Anahi mine in Bolivia.

Ametrine Description Ametrine History and Lore

No place else

There is only one commercial source for ametrine: the Anahi mine in Bolivia.


Nature’s gift

The presence of amethyst and citrine colors in a quartz crystal is a rare gift of nature.


Cutter’s choice

Ametrine’s colors blend, combine, and contrast uniquely in each gem.


Facts

  • Mineral: Quartz
  • Chemical composition: SiO2
  • Color: Bicolor orange/yellow and purple
  • Refractive index: 1.544 to 1.553
  • Specific gravity: 2.66 (+0.03/-0.02)
  • Mohs hardness: 7

Where It’s Found

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Treatments

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

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Synthetics

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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Imitations

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

1
Unique

No two ametrines look the same because the colors in each gem combine in a unique way.

2
Rare

There’s only one commercial source of ametrine, so the supply is very limited.

3
A Cutter’s Inspiration

Cutters delight in finding ways to maximize the beauty of ametrine.

Quality Factors

The following factors combine to determine ametrine’s value.

Color

quality factors

Fine ametrines show beautiful contrast between their orange and purple shades.

Clarity

quality factors

Faceted ametrine generally has no eye-visible inclusions.

Cut

quality factors

Unusual cutting styles add drama to ametrine’s unique color combination.

Carat Weight

quality factors

A wide range of sizes is available. Large material is popular with gem carvers.

Ametrine Quality Factors: The Comprehensive Guide

Research

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

Search of Ametrine

From the Andes to the Pantanál: In Search of Ametrine

Robert Weldon, GIA , Apr 30, 2013 Read Article
Bicolored Quartz

The Anahí Ametrine Mine, Bolivia

Paulo M. Vasconcelos, Hans-Rudolf Wenk and George R. Rossman , Mar 1, 1994 Read Article
Faceted Synthetic Ametrines

Russian Synthetic Ametrine

Vladimir S. Balitsky, Taijin Lu, George R. Rossman, Irina B. Makhina, Anatolii A. Mar’in, James E. Shigley and Shane Elen, and Boris A. Dorogovin , Jun 1, 1999 Read Article
Anahí Ametrine Mine Tunnel

Anahí’s “New” Ametrine

Robert Weldon , Mar 1, 2009 Read Article