Most gemstones have both a gemstone name and a mineral name, cross-listed in this pair of tables. Also, a state's official state mineral or state rock may be used as a gemstoneeven its state fossil. Be sure to check those lists, too.
Alabama: Star blue quartz (source)
Alaska: Jade (source)
Arizona: Turquoise (source)
Arkansas: Diamond (source)
California: Benitoite (source)
Colorado: Aquamarine (source)
Florida: Moonstone (source)
Georgia: Quartz (source)
Hawaii: Black coral (source)
Idaho: Star garnet (source)
Kentucky: Freshwater pearl (source)
Louisiana: Agate (source)
Maine: Tourmaline (source)
Maryland: Agate (source)
Massachusetts: Rhodonite (source)
Michigan: Chlorastrolite (pumpellyite) (source)
Minnesota: Agate (source)
Montana: Sapphire and Agate (source)
Nebraska: Blue agate (source)
Nevada: Turquoise and Fire opal (source)
New Hampshire: Smoky quartz (source)
New Mexico: Turquoise (source)
New York: Almandine garnet (source)
North Carolina: Emerald (source)
Ohio: Flint (source)
Oregon: Sunstone (source)
South Carolina: Amethyst (source)
South Dakota: Agate (source)
Tennessee: Freshwater pearls (source)
Texas: Topaz (source)
Utah: Topaz (source)
Vermont: Grossular garnet (source)
Washington: Petrified wood (source)
West Virginia: Fossil coral Lithostrotionella (source)
Wyoming: Nephrite jade (source)

