Sapphire Mining at Gem Mountain, Montana

We arrived at Jen and Eric’s House and the planning started! Jen and Eric had gone sapphire mining and of course we wanted to try our hand at it. She called and made reservations and the next day Eric drove us up and over the Sapphire Mountains to the entrance of the Gem Mountain Mine, (the road was gravel, and narrow with no guard rails and a cliff on one side of over six hundred feet).

The place was busy as many of the tables were occupied by other hopeful prospectors. We entered the Mine headquarters and paid for our buckets of mine material. The sapphires were mined from a placer deposit which was then passed through a trommel with three-centimeter holes. It was next hauled to the headquarters where we paid forty dollars per bucket.

Selecting our buckets. We carried them to our table and poured a shovelful into the screen shaker. One of the many helpers came over and showed us how to work the sifter. We first shook it to eliminate much of the dirt and then submerged it into the sluice water. Moving the screened box sideways, we rocked it which moved the material into a pile with the large rocks on top. Next, we rotated the box ninety degrees and repeated the process. The final step was to gently shake the material up and down forming an even spread of the cleaned gravels.

Finally, we carried it over to the table and quickly flipped it towards us. The sapphires are denser than the rest of the rock and so most of them are on top. Then the race was on as we both tried to spot and pick the sapphires. We them put them into the capped tube which had an elastic opening.

The process was very similar to the method used when mining for diamonds at the Diamond Mine State Park in Arkansas. Our first pan contained four small sapphires! Gently raking the material, we found another one. Now the process became tedious as we worked through our buckets. Most of the sapphires were small, less than a karat in size but we did find a larger one that was 1.34 karats. It took us two hours to go through both buckets. By that time my back was sore and we were ready to call it a day.

The last step was to pay five dollars to have our gems weighed and graded. Many of our stones were cuttable. While being cut the finished stone is about one third of the weight of the original gem. That’s typical and when we make our cabochons, we expect to lose about seventy percent of the original rough, (sawing into slabs, then into preforms, and finally shaping into the finished stone).

We are not going to have our sapphires cut/faceted, (too small), but we do plan on making them into a bracelet/pendant of the rough stones. We had fun, found our own gems, and next year hope to return. After all large sapphires are sometimes found, one of which was reported to be valued at twenty thousand dollars,(An average bucket contains fifteen karats, Jen and Eric got lucky and found sixty in their two buckets). Clear skies, (and clear gemstones)!