This article presents information about the CVD process, the history of its development, and properties that differentiate the resulting synthetic crystals from natural diamond.

The distinction of natural from cultured pearls traditionally has been based on X-radiography. X-ray computed microtomography (μ-CT) has recently been applied to gain more insight into pearl ...

Malaya garnets from Bekily, Madagascar, are predominantly pink to pinkish orange, with some stones orange to red. Discovered only in the late 1990s, the majority are intermediate members of the pyrope ...

View the holiday schedule for all GIA locations worldwide.

To commemorate the 50th anniversary of The Wizard of Oz, Harry Winston created real ruby slippers set with 4,600 rubies. - Courtesy Harry Winston Red is the color of our most intense emotions—love and ...

Figure 1. Pleochroism in a 15 ct tanzanite, as seen with the unaided eye through the crown and the pavilion sides and ends. Photo by Wimon Manorotkul. ABSTRACT While virtually all gemological texts ...

A highly saturated purplish pink to red pezzottaite from a new deposit in Madagascar is encountered in Tucson and tested by GIA researchers.

With the withdrawal of Soviet troops from Afghanistan, villagers in the Panjshir Valley are turning their attention to the emerald riches of the nearby Hindu Kush Mountains.

With the increasing use of radiation to color enhance gemstones, the issue of radioactivity has become a source of concern for gemologists worldwide.

Shopping for ruby, the July birthstone? Learn about its history, origins, care and cleaning, and where rubies can be found to help you pick the right one.

Peer Reviewed Gems & Gemology, Spring 2009, Volume 45, No. 1 Hackmanite/Sodalite from Myanmar and Afghanistan David Kondo and Donna Beaton ...

誕生石「アクアマリン」の意味 & 歴史 アクアマリンの語源はラテン語の「海水」です。古代の船乗りたちには、この宝石が波を落ち着かせ、彼らの海での安全が保たれるのだと言われていました。また、この3月の誕生石は幸せな結婚をもたらすとも考えられていました。ベリル (緑柱石)を身に ...