Article Search Results

Show Filters
Showing 103 results for "*"
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
Various Gems (Olivine - Rutile)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

Read More

Article
GIA Gem Project
Various Gems
(Sapphirine - Stibiotantalite)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

Read More

Article
GIA Gem Project
Various Gems (Taaffeite - Zoisite)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

Read More

Article
GIA Gem Project
Various Gems
(Danburite – Humite)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

Read More

Article
GIA Gem Project
Various Gems (Barite - Cuprite)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

Read More

Article
GIA Gem Project
Various Gems
(Kornerupine - Natrolite)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

Read More

 Spinel 80909 300x169
Article
GIA Gem Project
Spinel

Found in nearly every color – most notably red, pink and blue – spinels are popular gemstones because of their abundance, moderate cost and attractiveness.

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

Multi-colored gems are superimposed on an image of glacier peaks.
Article
Gems and Minerals from the Subarctic

Circumnavigate the boreal reaches of the globe to explore gems from polar regions.

Read More