Article Search Results

Show Filters
Showing 25 results for "*"
Article
Pyrope Garnet and Montana Sapphires Highlight Winter 2015 G&G

G&G Brief presents an overview of the content of the Winter 2015 issue of Gems & Gemology.

Read More

 Large open mussel shell with pink interior
Article
Freshwater Pearling in Tennessee

Natural pearl identification is one of the critical problems in pearl research. The DNA study of pearly mollusks and oysters facilitates solving this problem. To fulfill this goal, GIA sent a group from both research and education to Tennessee to sample the freshwater mollusks for DNA bar coding. Come with us to Camden, Tennessee, to see how we dive for pearly shells.

Read More

Sapphire fragments from the Sutara placer, Russia
Sapphires from the Sutara Placer in the Russian Far East

Studies the formation and chemical composition of the largely unexamined alluvial sapphires from Russia’s Jewish Autonomous District.

Read More

Article
Sapphire Mining Along the Upper Missouri River

A GIA team from Education and Lab Services visited the upper Missouri River sapphire deposits in Montana. The first sapphire discovery in the Treasure State, these deposits have been mined for over 150 years. The team witnessed the mining at the richest source, Eldorado Bar, and purchased a mine run to enrich GIA’s corundum collection.

Read More

Ruby and Sapphire Production and Distribution: A Quarter Century of Change
Ruby and Sapphire Production and Distribution: A Quarter Century of Change

During the past 25 years, the corundum market has been transformed from one of medium to high-priced gems to one that encompasses nearly all price ranges.

Read More

Rough and faceted sapphires from Rock Creek, Montana
Alluvial Sapphires from Montana: Inclusions, Geochemistry, and Indications of a Metasomatic Origin

Microscopic and chemical analysis may provide clues to the original source of Montana’s alluvial sapphires and help distinguish them from sapphires with overlapping properties.

Read More

Bright red faceted ruby in a gold ring, from the large and potentially productive Snezhnoe deposit in Tajikistan.
Rubies and Sapphires from Snezhnoe, Tajikistan

This large marble-hosted occurrence in the Pamir Mountains is a potentially productive source of corundum, including ruby with a bright red color reminiscent of “pigeon’s blood” Burmese rubies.

Read More

Article
Spring 2015 G&G Examines Blue Spinel, Chinese Jewelry Design and the Latest in Synthetics

G&G Brief presents an overview of the content of the Spring 2015 issue of Gems & Gemology.

Read More

Gem Mountain mining site
Article
Update on Rock Creek Sapphire Deposit

An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.

Read More

Article
Insights From Inclusions

Natural gemstones are typically far more valuable than synthetic ones, so being able to identify them correctly is a powerful skill.

Read More