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 ...

Birthstones are a fun, popular and colorful introduction to the world of gemstones. They appeal to audiences around the world regardless of gender, age, nationality or religion. Birthstones carry ...

A new deposit of scheelite was discovered in 1983 near Ratnapura, Sri Lanka. This article analyzes the gemological properties of this rare gem mineral, and compares them with those recorded for ...

Gems & Gemology, the professional quarterly of GIA, debuted in 1934. Appearing in the 306 th issue, this article looks back at the first 75 years. By reviewing the journal’s milestones, it also traces ...

The quest for the largest permeates all societies and disciplines. With the advent of new machinery and techniques, size records for faceted gemstones are falling constantly. Currently, a 22,898-ct ...

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 ...

The red variety of the mineral tugtupite, a rare silicate closely related to sodalite, has been used as a gemstone since 1965. This article presents the history of the mineral and details of its ...

Studies concerning the origin of color in gem materials have grown in sophistication in recent years, so that much new information is now available about natural color and its possible modification by ...

GIA laboratory-grown diamond reports includes a full quality assessment for laboratory-grown diamonds on the same scales as the GIA’s grading reports for natural diamonds. The specifications do not ...

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. This transformation was caused by the ...

The best ametrines show distinct areas of orangy yellow and purple. These colors are featured in this graceful cut design. Photo by Lydia Dyer, © John Dyer & Co ...

Though not characterized this way, there is almost a cradle-to-grave approach at work here. You can learn sources of information about jewelry, old and new, how to verify the nature and quality of the ...