Mining in Montana: Sluicing for Sapphires

The Berkeley Pit (by James St. John)

Montana has a rich history of resource extraction. The hill in Butte, MT was originally one of the most prosperous sources of copper as the electrification of the US started and WWII demanded this new technology. In 1920, this town (which in 2023 had about 40,000 people) held up to 100,000 people all working around the resource extraction biz until things became harder and harder to extract. Soon, “The Richest Hill” turned into an open pit mine, then a superfund site which kills any bird that lands in the pit’s heavy metal water and now a tourist attraction.

Resource extraction is so closely tied to Montana that a right “to a clean and healthful environment” was placed in the state constitution to protect its citizens. It was also a place for burgeoning union rights in the early 1900s and violence against organizers. The whole story is very well laid out in The Richest Hill podcast miniseries from Montana Public Radio.

So with a tip from our friends and a desire for a unique Montana experience we drove out to Gem Mountain Sapphire Mine near Philipsburg, MT to pan for some sapphires. I was at first a little doubtful that we’d find much, but they guarantee you will find 10-20 carats per $40 bucket. So with the help of some staff, we went searching:

  1. Pour out some gravel into a mesh box
  2. Sluice the gravel by rotating it and bouncing it in a water bath
  3. Dump out the pile of rocks now cleaned of mud and dirt
  4. Go through with a tweezers to pick out any sapphires and put them in a vile
  5. Dump the pile on the ground
  6. Continue until gravel bucket is empty

Indeed we did find 20 carats per bucket all in different sizes and colors (purple, blue, green). There was a whiteboard with the day’s highest carat find which was often around 7 carats. We had about six large-enough and high enough quality which could be heat treated to bring out the color and cut so they could be used in jewelry. This process was clearly where the mine was making its money as it was not inexpensive but it was really cool to have gems you found.

Cutting them apparently loses about 60% of the volume so you need at least a carat of material to start with. The person who evaluated our gems was a past ski instructor in Mammoth Lakes and for the Mountain Warfare Center nearby. In his words, if he isn’t mining for gold, he’s gambling and knows Reno well.

Finally on our way back from the gem mine we took a tour in Butte at the Orphan Girl Mine, which was a bit underwhelming given all the history we listened to via The Richest Hill podcast. It was a mine, but like all mines in Butte, they are flooded so you don’t really get to explore very much. We skipped paying to see The Pit superfund site which the Butte Chamber of Commerce is trying to charge for as a tourist attraction.

I left this day thinking maybe I don’t want to drink any more beer brewed in Montana after all these superfund sites, but then looking on the government’s website of cleanup sites… There are like 20x more sites in the East Coast then in Montana and I’ve also lived next to superfund sites in Silicon Valley. So, maybe I should have a bit less judgment. All in all, a really unique experience.

Went to Gem Mountain Mine (46.24728, -113.59158)