Quartz is a stone commonly found in the Gold country when looking for gold.
Grass Valley is known to be the location of the first quartz mine in California.
Tourmaline is found in Southern California in the San Luis Rey River Valley (near San Diego). Some of the highest grade tourmaline in the world has been mined from the mines located there.
State Gemstone: Benitoite
Benitoite is a rare blue stone named after where it was found, the San Benito River. It was officially adopted as the State Gemstone in 1985.
State Mineral: Gold
Much of California's history revolves around gold. So, it is not much of a surprise that California's state mineral is gold. It was officially adopted as the State Mineral in 1965.
State Rock: Serpentine
Serpentine was adopted as the official State Rock in 1965. Occassionally, gemstone dealers will try to pass serpentine off as Jade since it is a green non-translucent stone. Serpentine is a much softer stone and scratches easily.
Useful Books & Bibliography:
- Rockhounding California - by Gail A. Butler
A great guide to finding rocks and gemstones in California.
- Roadside Geology of Northern California (Roadside Geology Series) - by David D. Alt, Donald W. Hyndman
Geology of Northern California. There are no better books for roadside geologizing than the Roadside Geology series.
- Roadside Geology of Southern California (Roadside Geology Series) - by Robert P. Sharp, Allen F. Glazner
Geology of Southern California. There are no better books for roadside geologizing than the Roadside Geology series.
- Gemstones - by Cally Hall
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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