Listed below are the most important and/or plentiful gemstones found in each US State.

State	Gemstones Found
Alabama	Beryl, blue and yellow; Smoky Quartz, Hematite
Alaska	White Quartz, Jade
Arizona	Agatized wood (Petrified wood), Azur-Malachite, Turquoise, Garnet, Peridot, Jasper, Moissanite
Arkansas	Clear & Smoky Quartz, Diamond, Agate
California	Agate, Benitoite, Californite, Diamond, Citrine, Tourmaline, Abalone Pearl, Kunzite, Chrysoprase, Morganite, Jadeite, Jasper, Quartz, Turquoise
Colorado	Beryl, Aquamarine, Phenacite, Garnet, Amethyst, Agate, Citrine, Pyrite, Rose Quartz, Diamond, Fluorite, Topaz, Peridot, Quartz, Rhodonite
Connecticut	Beryl, yellow and green; Rose Quartz, Garnet, Tourmaline
Delaware	Pearl
Florida	Chalcedony, Conch Pearl
Georgia	Ruby, Beryl, Amethyst, Citrine, Garnet, Quartz
Hawaii	Peridot, Coral
Idaho	Garnet, Opal, Agate, Obsidian, Sapphire
Illinois	Fluorite, Pearl
Indiana	Obsidian, Pearl
Iowa	Fossil Coral, Pearl, Chalcedony
Kansas	Chalcedony
Kentucky	Pearl
Louisiana	Chalcedony
Maine	Tourmaline, Beryl, Rose Quartz, Pearl, Topaz, Amazonite, Clear & Smoky Quartz, Aquamarine
Maryland	Beryl, Clam Pearl
Massachusetts	Beryl
Michigan	Agate, Chlorastrolite, Hematite
Minnesota	Agate, Thomsonite
Mississippi	Pearl, Chalcedony
Missouri	Pearl, Fluorite, Pyrite, Calcite
Montana	Agate, Sapphire, Beryl, Amethyst, Smoky Quartz, Obsidian, Tourmaline, Garnet
Nebraska	Chalcedony, Pearl
Nevada	Rock Crystal, Citrine, Nevada Turquoise, Virgin Valley Black Fire Opal
New Hampshire	Beryl, Rock Crystal, Garnet
New Jersey	Smoky Quartz, Agate, Pearl, Prehnite
New Mexico	Turquoise, Garnet, Peridot, Rock Crystal, Obsidian
New York	Beryl, Brown Tourmaline, Rose Quartz, Fresh Water Pearl
N Carolina	Beryl, Aquamarine, Emerald, Almandite Garnet, Rhodolite, and Pyrope Garnet, Diamond, Cyanite, Hiddenite, Amethyst, Ruby, Sapphire, Smoky & Clear Quartz
N Dakota	Chalcedony, Agate
Ohio	Chalcedony, Fossil Coral
Oregon	Agate, Obsidian, Hydrolite, Sunstone
Pennsylvania	Amethyst, Almandite Garnet and Pyrope Garnet, Beryl, Sunstone, Moonstone
Rhode Island	Quartz, Amethyst
S Carolina	Beryl, Smoky & Clear Quartz
S Dakota	Beryl, Agate
Tennessee	Pearl
Texas	Beryl, Pearl, Tourmaline
Utah	Topaz, Garnet, Petrified Wood, Jasper, Obsidian
Vermont	Aquamarine, Pearl
Virginia	Amethyst, Garnet, Beryl, Moonstone
Washington	Agate, Pearl
West Virginia	Quartz
Wisconsin	Agate, Pearl
Wyoming	Agate (including Moss Agate), Jade, Ruby, Jasper, Bloodstone, Star Sapphire

Useful Books & Bibliography:

• Gemstones (Eyewitness Handbooks) - by Cally Hall, Harry Taylor (Photographer)
  A field guide to gemstones. Nice pictures and good, brief, well-written descriptions of over 130 varieties of gemstones.

• The Curious Lore of Precious Stones - by George Frederick Kunz
  The definitive book on fascinating, traditional gem lore. Very practical.

• Gem Identification Made Easy: A Hands-On Guide to More Confident Buying & Selling New 2nd Edition - by Antoinette L. Matlins & Antonio C. Bonanno
  This book is really great for knowing he latest gems, synthetics, treatments, and instruments. Easy to use.

• Gemstone Buying Guide: A Guide to Buying - by Renee Newman
  Very nice gemstone identification book.

• Simon and Schuster's Guide to Gems and Precious Stones - by C. Ciprianai, Kennie Lyman (Editor), Alessando Borelli
  This book is one inch thick and every facing page has a full colored photo of gems or precious stones. Hardness, weights, cuts, refractions, and value of color are given for each gem.

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