Outstanding in his field, Gemmologist Eric Emms, FGA, DGA, on his tour of Montana Sapphire mines.

The following is a review of Eric Emms’ Montana sapphire mining adventure.

“Hunting Montana Sapphires”
This past June, Eric Emms, well-respected British gemmologist, educator, and Hatton Garden gem trader, headed to Helena, Montana for the BrankoGems USA International Conference, all about exploring American gems, including pre- and post-conference trips to Yogo, Missouri River, and Rock Creek Sapphire Mines as well as Yellowstone National Park.

Emms’ latest blog, seen here, “Hunting Montana Sapphires,” takes us along for the ride — from the conference halls in Helena to the gravel bars of the Missouri River.

This photograph shows the area of the American mine on the east bank of Yogo Creek. Note the cleft where the Yogo Gulch cuts through the limestone cliffs.
Images by Eric Emms 

EXPLORING AMERICAN GEMS and gem experts will be discussing topics:
▻ “Rock Creek Sapphire Mine”, with Warren Boyd, Potentate Mining (Canada)
▻ “Origin Determination of Sapphires”, with Dr. Lore Kiefert, Gemmological Consultancy (Germany)
▻ “Turquoise 101”, with Joe Dan Lowry, Turquoise Museum (USA)
Other topics on portable instruments for ID Gems & Synthetic Diamonds, AI at conference include:
▻ “Gem Secrets: The Importance of Inclusions & CPF”, with Randall Lightfoot, Mayflower Estate Buyers & Consulting (USA)
▻ “Screening Instruments for Laboratory-grown Diamonds”, with Guy Borenstein, Stuller (USA)
▻ “An Update from GCAL by Sarine Lab: Diamond Traceability, AI-Driven Grading, and Market Dynamics”, with Sharrie Woodring, GCAL (USA)
▻ “How India’s CVD Boom in Production, Treatments and Cutting is Reshaping Diamond Mining and Gemological Testing Worldwide”, with Branko Deljanin, GRI (Canada)

Branko Deljanin, CGL lab (Canada), Conference Chair     info@brankogems.com
Travis Lejman, GAL (USA), Conference Co-Chair     travis@gemlab.com

A view of the Missouri river and mining on a bar.
Images by Eric Emms

Branko’s group included delegates from six countries and featured some serious presentations and even more serious hands-on fieldwork. The tour was guided by leading mining operators — George Lind of Roncor Corporation at the historic Yogo Gulch, and Warren Boyd of Potentate Mining at Rock Creek. in his blog, Emms describes venturing into mine tunnels, chipping at the walls of a Yogo sapphire mine, and observing the washing and hand picking of alluvial sapphire rough at Rock Creek.

A view of part of the highly mechanised extraction plant.
Images by Eric Emms

What makes Emms’ write-up even more special is that classic Eric blend of gemmological curiosity and field detail. He reflects on Montana’s two sapphire worlds — from the underground Yogo deposit, source of the famed “no-heat” Yogo sapphires, to the wide river terraces producing alluvial Montana sapphires typically enhanced by heat to bring out their signature blues and greens — and shares the kind of inclusion observations and crystal habits only a seasoned gemmologist would think to note. He even describes observing heat treatment demonstrations by heating specialist Dale Siegford.

Warren Boyd of Potentate Mining explaining to our group how the sapphire crystals are sorted
Images by Eric Emms

If you wanted to take the tour, but were unable to attend, you can now enjoy it through the eyes of Eric Emms — full of practical insights, personal observations, and a healthy dose of gemmological fun!

Note the typical shapes and colour of the sapphire crystals I picked out.
Images by Eric Emms

👉 Tap here ➜ to read Eric’s full post, “Hunting Montana Sapphires.”

… and while you are there, do check out his Instagram post – video from the mine sites!

Eric Emms, professional gemmologist and gem trader.

Tap here for information regarding the next BrankoGems International Gemmological Conference!

Roskin Gem News Report