Article Search Results

Show Filters
Showing 58 results for "*"
A woman sits in front of a computer screen with the DiamondView to her right.
Article
Inside De Beers’ Lightbox Diamonds

GIA researcher analyses and confirms that De Beers’ Lightbox diamonds are grown using the chemical vapour deposition process.

Read More

Drilled natural pearls examined in this study.
Saltwater Pearls from the Pre- to Early Columbian Era: A Gemmological and Radiocarbon Dating Study

Examines 85 saltwater natural pearls, reportedly harvested from the Caribbean islands off the coast of Venezuela during the early 16th century, to determine their age.

Read More

A blue synthetic star sapphire from past production of Wiede’s Carbidwerk
Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany

Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s until the 1970s.

Read More

Samples of by-product synthetic zincite
Characteristics of Gem-Quality By-Product Synthetic Zincite

Investigates the properties of synthetic zincite produced by industrial kilns in Poland.

Read More

10.08 ct HPHT synthetic diamond with color equivalent to Fancy Deep blue
Blue HPHT Synthetic Diamond Over 10 Carats

Results from GIA’s recent testing of a 10.08 ct blue HPHT synthetic diamond, the largest HPHT synthetic recorded to date.

Read More

Near-colorless and Fancy Vivid purplish pink CVD synthetic diamonds
Observations on CVD-Grown Synthetic Diamonds: A Review

Explores statistical data and defining characteristics of gem-quality CVD synthetic diamonds examined by GIA since 2003.

Read More

Gem Mountain mining site
Update on the Rock Creek Sapphire Deposit

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

Read More

Aquamarine necklace
Article
Exhibition Review: Maker & Muse, Women and Early 20th Century Art Jewelry

A review of the “Maker & Muse, Women and Early 20th Century Art Jewelry” exhibition at Chicago’s Driehaus Museum.

Read More

Gem Mountain mining site
Article
Update on the Rock Creek Sapphire Deposit

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

Read More

These two large synthetic diamonds were produced using HPHT growth methods by the Russian firm New Diamond Technology. The 4.30 ct specimen on the left has D color and SI1 clarity. On the right is a 5.11 ct sample with K color and I1 clarity. Photo by Wuyi Wang.
Article
Large HPHT-Grown Synthetic Diamonds Examined in GIA’s Hong Kong Laboratory

Examination of the largest HPHT synthetic diamonds GIA has examined so far demonstrated significant progress in this growth technology.

Read More