Back to gem encyclopedia

Ametrine

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

Responsive image
Golden Yellow

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

Responsive image
Lovely Purple

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

Responsive image
Blended shades

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

Responsive image
Responsive image
Bicolor

This quartz crystal shows both amethyst and citrine colors.

Responsive image
Top Quality

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

Responsive image
Rare

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

Responsive image
Tools

Overview

About Ametrine

About Amertine

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

Treatments

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

Learn More

Synthetics

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

Learn More

Imitations

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

Learn More
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.

Smoky Quartz Ametrine from the Yuruty Mine

Ametrine with Layers of Smoky Quartz

Dr. Michael S. Krzemnicki , Jun 1, 2000 Read Article
Ametrine from Yuruty, Bolivia

Update on Ametrine from the Yuruty Mine, Bolivia

Brendan M. Laurs , Mar 1, 2010 Read Article
Bolivian ametrine crystal.

Ametrine Optical Dishes: Windows into the Effects of Crystal Structure

Elise A. Skalwold and William A. Bassett , May 8, 2017 Read Article
A Selection of Faceted Natural Ametrines.

Using Conventional Equipment to Separate Natural from Synthetic Ametrine

Guy Lalous , Jul 25, 2014 Read Article

You are being redirected to GIA Alumni Association, LLC.

5