GIA’s Winter 2025 Gems & Gemology (G&G)

GIA’s Winter 2025 Gems & Gemology (G&G) issue is now available—online and in print. Fittingly, GIA describes this issue as one where “colored stones step into the spotlight”—and after Tucson, that’s hard to argue with.

In the feature articles section, one paper in particular feels especially timely. Montana sapphires were clearly having a moment across several shows, and this study takes a closer look at where some of that material may actually be coming from:

The Primary Sapphire Occurrence at French Bar Sill Along the Missouri River, Near Helena, Montana
Robert E. Kane, Kory L. Pettman, Aaron C. Palke, Rachelle B. Turnier, Richard B. Berg, Nathan D. Renfro, and Christopher P. Smith

In the lead paper, a team led by Bob Kane examines a primary sapphire occurrence at the French Bar sill—only the second known source of gem-quality sapphire in Montana outside of Yogo Gulch—a detail that alone makes this worth a closer look.

What makes this especially interesting is how the material compares to what we already see in the market. The study shows that sapphires from this primary source share overlapping inclusion patterns and trace element chemistry with stones from Montana’s secondary deposits—raising some interesting questions about origin assumptions—and how these stones are interpreted in the trade.

Also featured in this issue are studies on emeralds from Shaanxi, China, and turquoise from Arkansas’s Mona Lisa mine—continuing the strong emphasis on colored stones.

As always, G&G’s regular sections—Lab Notes and Micro-World—offer their usual mix of the unusual and the educational.

But what really caught our attention this issue is the coverage from last year’s AGS/GIA Converge conference.

As GIA notes, this issue offers “a glimpse into some of the engaging research presentations from Converge 2025 in Carlsbad, California,” along with updates from the GIA Museum’s latest exhibit.

A Visit to the GIA Museum
That exhibit, by the way—Temples and Treasures of Southeast Asia—is also featured in the In the Spotlight section, highlighting the crystals and gems central to the region’s cultures. And it is still on display at GIA’s Carlsbad campus, but only through next month – April 2026.

Having attended Converge, we can tell you—there’s a lot here worth your time. More than a few of these presentations could easily stand on their own as full seminars. And don’t skip the Poster Presentation summaries. Some of the most interesting work at the conference was happening in that room—definitely worth a closer look.

Rather than picking our favorites for you, how about you set aside a little time, and browse. We’re sure you’ll find something worth your attention.

And remember—this issue, along with every issue of Gems & Gemology dating back to 1934, is available at no cost on GIA’s website. at GIA.edu.