Gemstones: California’s earthen treasures

This balmy state is a virtual treasure trove, filled with places to do some serious gemstone hunting

It has been said that “all that glitters is not gold.” This is a truism, because what you see could be a diamond, an amethyst or a sapphire. These are gemstones. Getting tired of seeking your fortune at the casino? Want to play in the dirt or out in the fresh air? Try your luck at gem hunting. California has a wide variety of precious and semi-precious stones; in fact, the state ranks as one of the leading gemstone regions in the world. We will tell you what they are, and maybe point you in the right direction—you can take it from there.

Some characteristics of gemstones are rarity, hardness and lustre. Western man has, in the past, divided gemstones into precious and semi-precious categories according to the rarity of the gem. Nowadays, although rarity is important, it is not the only determining factor of a stone's value. Flaws or inclusions lower the value. “Water,” which refers to the gem’s lustre, transparency or brilliance will also dictate its value. “First water,” transparency is better than “second water” or “third water.”

What is your fancy? Pink, red, blue, green, clear? Hard like a diamond or uncommon like the state gem, benitoite? Discovered in 1906, benitoite, (ben-EE-toe-ite) is one of the rarest and most valuable gemstones in the world. It is found in hydrothermally altered serpentinite. Benitoite is found in the vicinity of the Dallas. The Benitoite Gem Mine in San Benito County, California, offers the chance to find this gem. They charge $70 per person or $35 for seniors with current rockhound membership from any federation club.

Not all gemstones are used in jewelry (a spectacular example of gems as clockworks can be found in San Diego,
where a jeweller named Joseph Jessops constructed a large clock, 21 feet tall, made of various gems). Some, like agate or jade for instance, are carved into mystical figures.

Go on a rock hunt

Hunting or fishing for rocks: is it a pleasant pastime, a lucrative endeavor or an indication that you have lost it and gone over the edge? Well, some might think the latter, until you find ice, a pretty green stone or a nugget. I’m talking diamonds, emeralds or gold. Got your attention now, right? California abounds in earthen treasure. You just need the interest, knowledge and perseverance.

People have found gemstones throughout the state, but southern California, especially the San Diego area, seems to have quite a variety—as does Arizona. Get to know what the gem looks like in the rough and where it is most likely to be found. Quartz is often found near gold.

Streams and bends in a river might wash over gold. Do some research as to the type of terrain and what equipment you might need and find out who owns the land and if you can hunt for rocks on that property. If nothing else your search will provide you with interesting fodder for conversation. As the English used to say, “you can dine out on it (the experience) for months.“

Where to look:

• Agate in the deserts.
• Amethyst in Acton, Los Angeles.
• Benitoite along the San Benito River in San Benito County.
• Beryl in the mountains north of San Diego.
• Diamonds in Volcano, Amador County, at the junction of south fork of Yuba River. By a rough estimate, 500 diamonds have been found—mostly in the Sierra foothills. They have also been found in Jackson Gulch in Amador County.
• Jade near Indio, northeast of Joshua Tree National Monument at Storm Jade Mountain Mine.
• Jasper near Baker, San Bernardino County, in the Owl Head Mountains; in Afton Canyon; near Barstow, San Bernardino County off of Mule Canyon Road; Fort Irwin road heading north, then to Superior Valley two miles north to a faint road that goes for a quarter mile. They are found in a wash and on the hillside.
• Kunzite in Pala, San Diego County; in the Chief Mountains 60 miles north of San Diego.
• Obsidian near Calipatria, in south-central California.
• Pink beryl can be collected from the Little Acorn Mine in the Greenhorn Mountain District of Kern County.
• Quartz crystal found in streambeds in Amador and Calaveras counties. It is commonly found in gold country. The Mokellumne Hill area has produced the best in the past. Hiriart Hill in San Diego County has fine-quality rock crystal.
• Rose quartz and agate near Greenhorn Mountain Park. Obtain permission at the park office.
• Smokey rose quartz near Hemet in Riverside County at the Williamson Mine, just south of Juan Diego flat.
• Tourmaline—California has had very high value tourmaline with deposits in Riverside and San Diego counties, greater than any other deposits in the northern hemisphere. San Luis Rey River Valley near San Diego is a good place to look.
• Topaz in the Pala District of San Diego County.
• Turquoise in San Bernado, Imperial and Inyo County.
• Travertine at Furnace Creek, Inyo County Highway 190 N, 13-¾ miles to an abandoned quarry west of the road and one mile east of Death Valley Monument. Also in a ravine half a mile further north. NOTE: There is no collecting permitted within Death Valley Monument.

Always contact the Bureau of Land Management (BLM) for any fees or permit requirements before hunting on public land. Get permission from land owners before hunting on private property.

Tools needed: Pick axe, rock hammer, gloves, safety glasses, bucket, layered clothing, water, hat and sunscreen

Tell someone where you are going and when you expect to return.

While not considered a gemstone, geodes—round rough rocks formed by millions of years of volcanic activity—can be opened to reveal a sparkling crystal interior, and are considered valuable by many people. Riverside & Imperial Cos. Are easy places to find them. Geodes in Blythe, California, are harder to get to, but worth the journey.

Editor's Note: calstategemmine.com is a good source for locating gems, as is digforgems.com.

Resources

Benitoite Gem Mine, 48242 Los Gatos Road, Coalinga, California, 93210. Phone: 559-935-5909

Oceanview Mine, Chief Mountain, Magee Road, Pala, California. Phone: 760-415-9143