How to Find Garnets in Montana

Find the best area. The United States Geological Survey provides a map of the area surrounding the Sweetwater Garnet Mine and the Beaverhead National Forest where garnets are most likely to be. According to the Montana Bureau of Mines and Geology, several mines are in operation, so be sure you know where they are and where you are allowed to search.

Always know where you are. If you are on federal land, be sure you are allowed to take what you find. Never trespass. If you want to collect on private land, be sure to ask the owners if they allow rock hunting. Find out if they have any rules they want you to follow while on their land.

Look for metamorphic rocks. Most minerals are formed in metamorphic rock, or rock that has undergone change via immense pressure and heat. Garnet is found most commonly in gneiss, amphibolite and schist.

Look for erosion. According to the USGS, garnet deposits are often found where water has moved rock and gravel down eroded metamorphic rocks.

Get out your magnet. The magnetic properties of garnet make it easy to find in a pile of eroded rubble by running a magnet over the debris. Unpolished garnet crystals will be easily visible in the broken rock.