Agate hunting is a popular sport along the banks of the Yellowstone River, and it’s a fun way to spend an afternoon. The agates found in this area are popular worldwide, due to their high quality.
Agate is translucent and often has unique patterns embedded into the interior of the rock The outside of the rock is rough and the rock is usually tan or gray in color. Most of the rocks are found in gravel deposits in the hills surrounding the Yellowstone River, and on the gravel beds in the river. The Agate hunting season is from early spring through the fall.
Agate is formed when the igneous rock layer cools and leaves behind gas bubbles. The bubbles are later filled with mineral-rich water and silica solution that hardens and creates a colored layer. The layers build up creating the agate. The agates found in Montana are often referred to as Montana Moss Agate or Plume agates.
For more information on where to begin your hunt, contact the local area Chambers of Commerce. Guided hunts are also available.