Article Search Results

Show Filters
Showing 4 results for "*"
Article
GIA Gem Project
Beryl

Chemically pure beryl is colorless, but trace elements give rise to green, blue and pink/red colors.

Read More

Article
GIA Gem Project
Corundum

Ruby and sapphire (usually blue, but also in every other color) have been the most important colored gemstones for several thousand years. Originating historically in southeast and central Asia, and more recently in eastern Africa, these colored varieties of the mineral corundum have been much sought as gems because of their rarity, color and durability. Gem corundum can display asterism and chatoyancy due to the presence of oriented mineral inclusions, and in some cases, a change of color when viewed under different light sources.

Read More

Article
GIA Gem Project
Corundum

Ruby and sapphire (usually blue, but also in every other color) have been the most important colored gemstones for several thousand years. Originating historically in southeast and central Asia, and more recently in eastern Africa, these colored varieties of the mineral corundum have been much sought as gems because of their rarity, color and durability. Gem corundum can display asterism and chatoyancy due to the presence of oriented mineral inclusions, and in some cases, a change of color when viewed under different light sources.

Read More

A Status Report on Gemstones from Afghanistan

An overview of the plentiful and various gem materials being discovered and produced in Afghanistan.

Read More