Gemstones Found in Idaho

      Garnet is found in Idaho's mountains.


      Opal is found in southeastern Idaho. One famous mine is Spencer Opal mine located about 70 miles West of Yellowstone National Park. The mine was discovered by hunters in 1948, and filed on as a mining claim in 1952. The primary formation of the mine is a rhyolite and obsidian flow, full of gas pockets. The opal solution, a silica, was a secondary deposit caused by geyser activity, which settled in the gas pockets. As a result of many eruptions over a long period of time, the opal lays in layers. Most of the layers are very thin, resulting in some of the most brilliant and beautiful triplet opal in the world. Opal information courtesy of A Stone Age

    Other gemstones found in Idaho are: Agate, Obsidian, and Sapphire.

Idaho State Gemstones

    State Gemstone: Star Garnet
    Star Garnet was adopted as Idaho's State Gemstone on 1967. When Star Garnet has a 6 ray star (rather than the more common 4 ray star), it is considered more precious than either Star Rubies or Star Sapphires.

Useful Books & Bibliography:

Idaho State Information