The Complete Amethyst Guide

Table of Contents

  1. Amethyst Consumer Information
  2. Amethyst References in Antique Gemological Books

Amethyst Consumer Information

As provided and validated by various gemmological organizations, laboratories and the "World Jewelry Confederation CIBJO"

Care

Care should be taken not to knock the gem during use, as small fissures or cracks may develop, especially along facet junctions. It can be cleaned with warm, sudsy water or a dampened cloth. Some amethysts may lighten in tone over time upon prolonged exposure to bright light.

Clarity

Some amethysts have liquid inclusions containing solids and gases (water bubbles)
Some minerals suchas rutile and hematite can be found in amthyst as well

Color

Transparent to translucent lilac to purple through bluish purple
A reddish purple colour-shift that is sometimes visible in incandescent light
In ametrine, a unique form of quartz mined from a single locality in Bolivia, the colours are both yellow and purple in areas of zoning. Such gems are sometimes cut in a way that mixes the colours, and at other times to show the division of colours

Treatment

Amethysts are heat treated to improve an overly dark purple color or to get rid of the smoky color
Many amethysts in the market are synthetic. It is virtually impossible to differentiate the two

Cut

Amethyst can be found in many sizes and therefore offered in many different kinds of cuts and carvings
Many famous lapidaries (cutters) work with amethysts to make unusual carvings or cuts, which are also highly prized.
Bi-coloured ametrine has been skillfully or cleverly carved to emphasize the bi colored nature of the stone

Collect

Collectors of amethyst look for depth of the purple colour with red flashes if the gem is cut conventionally. Many famous lapidaries (cutters) work with amethysts to make unusual carvings or cuts, which are also highly prized. Because the bi-coloured ametrine comes from only one mine in the world, it is sometimes collected if the depth of colour and the division of colour is strong, or if it has been skillfully or cleverly carved.

Amethyst References in Antique Gemological Books

Amethyst References before 1800

Amethyst extremely valuable before large Amethyst finds in Brazil in 19th century.
One of the world’s first systematic overviews of gemstones and minerals (Nicols 1652) on Amethyst.
Agricola: Hyacinthus, Amethyst and Wine.

Amethyst: Talismans and Cardinal Stone

High Priest Breastplate and Amethyst here
Amethyst listed in several cultures as one of talismanic stones.
Valentine’s day: St. Valentine wearing an Amethyst ring.
Engraving heightens Amethyst effect.

Comprehensive Amethyst Chapters

THE Amethyst reference: Intaglios, engraved gems, Greeks, Romans, Renaissance.
Short Amethyst Overview

Classic Amethyst Localities

Amethyst locations in Spain, Siberia and Brazil (1871)
Bohemian Amethyst (1865)

Oriental Amethyst = Pink Sapphire

What is Oriental Amethyst (Tavernier in 17th century). Also Castellani.
Treatments, Quality of Oriental Amethyst.
Engraved Oriental Amethyst (Greeks to French Crown Jewels)