◂ BACK TO GEM ENCYCLOPEDIA

Ametrine

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

Ametrine
See Gem As

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

TREATMENTS

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

SYNTHETICS

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

IMITATIONS

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

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
Ametrine from Yuruty, Bolivia
Update on Ametrine from the Yuruty Mine, Bolivia
Brendan M. Laurs , Mar 1, 2010
Bolivian ametrine crystal.
Ametrine Optical Dishes: Windows into the Effects of Crystal Structure
Elise A. Skalwold and William A. Bassett , May 8, 2017
A Selection of Faceted Natural Ametrines.
Using Conventional Equipment to Separate Natural from Synthetic Ametrine
Guy Lalous , Jul 25, 2014

Recommended Reading

reading

Amber: the Golden Gem of the Ages
Patty C. Rice

reading

Amber: Window to the Past
David A Grimaldi

You Might Also Like

YMAL AJP
AJP®: New 5-Day Program Offered Worldwide
Learn About NextGem
GIA NextGem™ Diamond Training for Retail
Explore GIA Laboratory Promotional Offers
Explore GIA Laboratory Promotional Offers
Shop the GIA Store
Shop the GIA Store
Ametrine Gemstone | Natural Ametrine Stone - GIA