In some cases, the value of a sapphire depends strongly on its geographic origin. This article details the origin data GIA has collected for blue sapphire and describes its methodology for using the ...

The Hope diamond, the Dresden Green, the Idol’s Eye, the Portuguese Diamond and the Moussaieff Red – these famous diamonds are spectacularly beautiful jewels that have been admired for centuries. An ...

Thousands of years ago, red garnet necklaces adorned the necks of Egypt’s pharaohs, and were entombed with their mummified corpses as prized possessions for the afterlife. In ancient Rome, signet ...

Dr. Sally Eaton-Magaña is senior manager of diamond identification, and Dr. Matthew F. Hardman is a research scientist, at GIA in Carlsbad, California. Dr. Shoko Odake is senior manager of diamond ...

CARLSBAD, Calif. – June 2, 2025 – Beginning later this year, GIA (the Gemological Institute of America) will start using descriptive terms to characterize the quality of laboratory-grown diamonds and ...

April’s birthstone. The hardest natural substance on Earth. More than a billion years old. There’s a wealth of history and knowledge surrounding diamonds. This popular gem is brilliant, glamorous, ...

Photoluminescence (PL) spectroscopy is frequently mentioned in the gemological literature, but its relevance to the wider trade audience is rarely discussed. Due to the possibility of an undisclosed ...

Explore jade history, research, quality factors, and more in the GIA Gem Encyclopedia.

Seen in practically every color of the rainbow, colored diamonds are far rarer than diamonds in the D-to-Z color range. Only one out of 10,000 carats of fashioned diamonds displays fancy color, and a ...

Dr. Malczewski is a nuclear physicist and assistant professor at the Institute of Earth Sciences of the University of Silesia (Poland), specializing in the field of natural and anthropogenic ...

This bench trick focuses on fine cable and rope chains with tiny links made from extremely thin wire. It is difficult to manipulate these links, reconnect them and then solder them. Study the chain to ...

Field reports, videos, photography, and firsthand accounts from mines and industry hot spots around the world.