The GIA Laboratory-Grown Diamond Report includes full quality assessment with a plotted clarity diagram. Color and clarity specification are described on the same scale as the GIA Diamond Grading ...

The unique beauty of gem sapphires from Kashmir has brought fame to a locality about which little has been reported in recent years. After an initial burst of activity 100 years ago, the production of ...

Success in the gem and jewelry industry requires keeping abreast of gem discoveries, new treatments and synthetics and their detection, and evolving technologies. The 2018 GIA Symposium – “New ...

Two new deposits of Cu-bearing tourmaline have been found in Paraíba State, Brazil, not far from the original source at Mina da Batalha. The Glorious mine has produced a limited amount of gem-quality ...

Pictured above, a South Sea cultured pearl containing an RFID tag, an RFID reader, and a GIA Cultured Pearl Classification Report describing the RFID reference number. Fukui Shell Nucleus Factory uses ...

CARLSBAD, California – September 23, 2024 – Everything retailers and their customers need to know about diamonds just got easier to find and understand with GIA’s redesigned consumer-facing website ...

钻石有着悠久的历史，是人们梦寐以求的珍品。 公元一世纪，古罗马博物学家普林尼（Pliny）说：“钻石不仅是宝石中最有价值的，而且是这个世界所有事物中最有价值的。“ 一颗钻石在最终 ...

As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated.

This 5.30-carat emerald from Brazil has a slightly bluish green color. Courtesy John Parrish, courtesy African, Brazilian, Colombian Gems Incorporated. Emerald has many special qualities, but colored ...

GIA has studied more than 400 important gemstones in the Edward J. Gübelin Gem Collection and is committed to sharing this repository of gemological information. Dr. Edward Gübelin’s lifelong study of ...

Blue diffusion-treated sapphires are becoming more prevalent than ever before. The diffusion technique, which involves the addition of color-causing chemicals during heat treatment, results in a thin ...

Figure 1. A single tourmaline fiber contains three distinct chemical zones, each recording the fluid composition at the time of growth. Between zones, fluids dissolved preexisting tourmaline to ...