
Rockhounding California
California is an extraordinary state for rockhounding. Geological forces have created one of the widest varieties of rocks and minerals found in any state. The state, also known as the ‘Golden State,’ is home to amazing national parks (Yosemite, Lassen, Death Valley, & Joshua Tree) and national monuments (Devils Postpile & Lava Caves) as well as thousands of historic gold mines. Aside from gold, California long has been famous for fantastic tourmaline deposits as well as obsidian. In addition, California has numerous minerals, gemstones, and fossils as well as oil and gas deposits. The Rancho La Brea Tar Pits is one of the world's most famous Ice Age fossil sites. The state also is the site of the second largest meteorite found in the United States.
State Rocks, Gemstones, Minerals, Fossils, & Dinosaurs
Rockhounding Tip: Knowing state rocks, gemstones, minerals, fossils, and dinosaurs often can be very useful information for rockhounders. Ordinarily, states with significant mineral deposits, valuable gemstones, fossils, or unusual or significant rock occurrences will designate an official state mineral, rock/stone, gemstone, fossil, or dinosaur to promote interest in the state’s natural resources, history, tourism, etc. Accordingly, such state symbols often are a valuable clue as to potential worthwhile rockhounding opportunities.

Serpentine
State Rock: Serpentine (1965)
California was the first state to
designate an official state rock. In
1965, California designated Serpentine as the official state rock. Serpentine
is apple-green to black in color and is often mottled with light and dark
colored areas. It has a shiny or wax-like appearance and slightly soapy feel. Serpentine usually is fine-grained and compact
but may be granular, platy, or fibrous.
It occurs in central and northern California – in the Coast Ranges,
Klamath Mountains, and Sierra Nevada foothills.
Serpentine primarily is composed of one or more of the three magnesium
silicate minerals: lizardite, chrysotile,
and antigorite. Serpentine is
metamorphic and/or magnesium-rich igneous rock, most commonly peridotite, from
the earth’s mantle. In 2010, a few California legislators
attempted to pass legislation to remove serpentine as the official state rock
because the rock (which occurs in 42 of California’s 58 counties) contains very
small amounts of naturally occurring asbestos – much like many other natural
resources. The bill (SB 624) passed the
state senate, but then failed to pass the state house.

Benitoite
State Gemstone: Benitoite (1985)
California designated benitoite as the
official state gemstone in 1985. Sometimes
called the 'blue diamond,' benitoite was named in
1907 after the river (San Benito River), county, and nearby mountain range where it was
found. "Benito" is a spanish
form of benedictus, meaning blessed. The barium-titanium silicate gem is extremely rare and ranges in color from a
light transparent blue to dark, vivid sapphire blue, and occasionally it is
found in a violet shade.
Gem quality benitoite is
found found only in San Benito County, California. The crystals form as well-defined triangles as
seen in this specimen.

Native Gold
State Mineral: Native Gold (1965)
California designated native gold as
the state mineral in 1965. The accidental discovery of
gold in 1848 at Sutter’s Mill in Coloma started a bonanza that brought
California fame and gave it the title of the “Golden State.” The Gold Rush of 1849 (which was not the
first gold rush in America) and the subsequent influx of settlers led to
California becoming the 31st state in 1850.
In the four years following the
discovery of gold by James Marshall in January of 1848, California's population
swelled from 14,000 to 250,000 people. Miners
came from all over the world and extracted 28,280,711 fine ounces of gold from
1850 – 1859 that would be worth over ten billion dollars today. There
are thousands of historic gold mines throughout California. Although production is much lower, present day prospectors still may pan
for gold in California's streams. Gold
is used mainly as currency, jewelry, in scientific instruments, and in dental
applications.

A Saber-tooth cat fossil … and me in 2011 at the Natural History Museum of Los Angeles County
State Fossil: Saber-Tooth Cat (1973)
California designated the saber-tooth
cat (Smilodon californicus) as the official state fossil in 1973. The
carnivorous saber-tooth cats (extinct members of the cat family Felidae)
flourished throughout North America from the late Eocene and early Oligocene
(40 to 35 million years ago) until the close of the Pleistocene about 11,000
years ago. In California, the cat’s
fossilized remains are most abundant at the La Brea Tar Pits (late Pleistocene)
in Los Angeles where more than 2,500 fossilized specimens
have been found. Fossil evidence indicates that this ice age member of
the cat family with 8-inch upper canine teeth was somewhat shorter than a
modern lion, but weighed more.

State Prehistoric Artifact
State Prehistoric
Artifact: Chipped Stone Bear (1991)
California also has an official state
prehistoric artifact, the chipped stone bear.
Discovered at an archaeological dig site in San Diego County in 1985,
this small stone object measures about 2 1/2 by 1 1/2 inches and resembles a
walking bear. Fashioned from volcanic
rock by one of California's earliest inhabitants some 7-8,000 years ago, the
stone artifact is thought to have been made for religious use. The Legislature named the chipped stone bear a
state symbol in 1991 making California the first state to designate an official
State Prehistoric Artifact.
Rockhounding Resources

State-specific rockhounding books (including the books listed here as well as other books), regional rockhounding site guides, and other helpful rockhounding resources are identified - by category - in the Books & Gear section of Gator Girl Rocks with a link to the Gator Girl Rocks Amazon Store where you may easily browse selected resources and securely place an order. Your order will benefit Charity Rocks!


U.S. Bureau of Land – California
The BLM manages over fifteen million acres of
federal public lands in the state of California.
- Vinson Brown, David Allan, & James Stark, Rocks and Minerals of California (3d ed. 1987).
- David D. Alt & Donald W. Hyndman, Roadside Geology of Northern and Central California (2000).
- Allen F. Glazner & Robert P. Sharp, Geology Underfoot in Southern California (1993).
- Allen F. Glazner & Robert P. Sharp, Geology Underfoot in Death Valley & Owens Valley (1997).
- Allen F. Glazner & Greg Stock, Geology Underfoot in Yosemite National Park (2010).
- James R. Mitchell, Gem Trails of Northern California (2d ed. 2005).
- James R. Mitchell, Gem Trails of Southern California (Rev. ed. 2003).
- Gail A. Butler, Rockhounding California (2d ed. 2012).
- Katherine J. Baylor, California Rocks:A Guide to Geologic Sites in the Golden State (2010).
- Delmer Ross, Rockhounding the Wiley’s Well District of California:The GPS User’s Guide (2006).
- William Estivillo, Gems & Minerals of California:A Guide to Localities (1992).
- B.J. Tegowski, Easy Field Guide to Invertebrate Fossils of California (1995).
- Allan W. Eckert, Earth Treasures Vol. 4A – Southwestern Quadrant (1987; reprint in 2000).
- James Martin Monaco & Jeannette Hathway Monaco, Fee Mining & Rockhounding Adventures in the West (2d ed. 2007).
- Kathy J. Rygle & Stephen F. Pedersen, Southwest Treasure Hunter's Gem & Mineral Guide (4th ed. 2008).
Museums of Interest to Rockhounders

That's me - and my younger cousin - at the Natural History Museum in 2011
Natural History
Museum of Los Angeles County
Los Angeles,
California
The Museum, located next to the University
of Southern California, includes the well known Gem & Mineral Hall, which
displays more than 2,000 spectacular specimens and is one of the finest
exhibits of gems and minerals in the world.
The hall features one of the largest gold exhibits in the world that
includes over 300 pounds of natural gold along with gold mining artifacts and
other memorabilia. In addition, the
museum’s Dinosaur Hall, which is one of the most
extraordinary dinosaur exhibits in the world, exhibits more than 300 real fossils
and 20 complete dinosaurs and ancient sea creatures.

Page Museum
Rancho La Brea Tar
Pits – Los Angeles, California
Rancho La Brea is one of the world’s
most famous fossil localities, recognized for having the largest and most diverse
assemblage of extinct Ice Age plants and animals in the world. Visitors can learn about Los Angeles as it was
between 40,000 and 10,000 years ago, during the last Ice Age, when animals such
as saber-tooth cats and mammoths roamed the Los Angeles Basin. Through windows at the Page Museum Laboratory,
visitors can watch bones being cleaned and repaired. Outside the Museum, in Hancock Park, life-size
replicas of several extinct mammals are featured.

San Diego Natural
History Museum
San Diego, California
The museum, located in Balboa Park, is one of
the oldest in the Western United States.
The museum exhibits rocks, minerals, gemstones, and fossils.

University of California Museum of Paleontology
University of California – Berkeley, Berkeley,
California
UCMP has the largest paleontological
collection of any university museum in the world. A limited number of fossils are
exhibited. The museum, however, has
online exhibits.

California Academy of Sciences
Golden Gate Park – San Francisco, California
The Academy’s Kimball Natural History Museum
exhibits a cast of a Tyrannosaurus rex.


Fricot Nugget
California State Mining & Mineral Museum
Mariposa, California
The California State Mining & Mineral
Museum is a California State Park. The
museum’s collection, which began in 1880,
contains over 13,000 objects including mining artifacts, rare specimens of
crystalline gold in its many forms, as well as beautiful gem and mineral
specimens from California and around the world. The
museum exhibits the Fricot ‘Nugget,’ a rare and beautiful specimen of
crystallized gold discovered in the American River in 1864. This spectacular 13.8-pound specimen is the
largest remaining intact mass of crystalline gold from 19th century California.

Fossil Discovery Center of Madera County
Chowchilla, California
The Fossil Discovery Center is across
the street from one of the
largest middle-Pleistocene fossil excavations in North America. The site was discovered in 1994 when a
million-year old Columbian Mammoth tusk was found as workers were scraping dirt
at the Madera County landfill in Fairmead.
Scientists realized that this County dump was located on one of the most
significant fossil beds discovered from the Pleistocene period. In addition to mammoths, fossils have been
found from saber tooth cats, giant ground sloths, camels, horses and rare
prong-horned antelopes, as well as smaller animals. Thousands of fossils have
been recovered from the site.
Raymond M. Alf Museum of Paleontology
Claremont, California
The museum’s ‘Hall of Life’ exhibit traces the history of life on earth through exhibits
spanning the first cells through human civilization and includes a variety of
fossils. In addition, the museum’s ‘Hall
of Footprints’ exhibit is the largest, most diverse collection of animal
footprints on display in North America and also includes a variety of fossils.

San Bernardino County Museum
Redlands, California
The museum exhibits minerals, gemstones, and
fossils.

Santa Barbara Museum of Natural History
Santa Barbara, California
The museum’s Geology & paleontology Hall
exhibits a variety of fossils including a
19,000-year-old toothed bird, a Miocene giant toothed whale, and the Channel
Islands pygmy mammoths. In addition, the museum’s Mineral & Gem
Gallery exhibits a variety of minerals, gemstones, and crystals.

Fallbrook Gem & Mineral Society Museum
Fallbrook, California
The museum exhibits rocks, minerals, gemstones,
and fossils from San Diego County as well as around the world.

Buena Vista Museum of Natural History
Bakersfield, California
The museum exhibits Miocene fossils from
Shark Tooth Hill in Kern County, California.

Boron Twenty Mule Team Museum
Boron, California
The Twenty
Mule Team Museum exhibits mining artifacts and historic memorabilia pertaining
the history of borax mining in Boron and Death Valley. Borax
was first discovered in California in 1881. Borax had been important in small
quantities for thousands of years in gold smithing and ceramics.

Borax Visitors Center
North of Boron, California
The Borax Visitor Center looks down on the
largest open pit mine in California, measuring one and a half miles long, three
quarters of a mile wide, and 650 feet deep.
The site, in the Mojave Desert, is one of the biggest and richest
deposits of borax on the planet.
Places to Visit - Interesting Sites To See

Lassen Peak
Lassen Volcanic National Park
Northeastern California
Lassen Volcanic National Park’s dominant
feature is Lassen Peak, the largest plug dome volcano in the world and the
southern-most volcano in the Cascade Range.

Crystal Cave - Sequoia National Park
Sequoia & Kings Canyon National Parks
Fresno County, California
Sequoia & Kings Canyon National Parks, in
addition to including the highest point in the continental 48 states (Mount
Whitney), include over 200 caves including California’s longest known cave
(Lilburn Cave). The caves, like most caves in the Sierra Nevada of California,
are mostly solution caves dissolved from marble. Boyden Cavern, a commercial fee-access karst
cavern, also is located within the boundary of the parks.

A 'Sliding Rock' at Racetrack Playa in Death Valley National Park
Death Valley National Park
California/Nevada
One interesting mystery of
Death Valley National Park is the sliding rocks at Racetrack Playa (a playa is
a dry lake bed). These rocks can be
found on the floor of the playa with long trails behind them. Somehow these rocks slide across the playa,
cutting a furrow in the sediment as they move.

We went to Lava Beds National Monument in 2011. It was awesome.

One of the lava tubes at the National Monument
Lava Beds National Monument
Northeastern California
Lava Beds National Monument, which lies on the
northeastern flank of the Medicine Lake Volcano, is well known for its numerous
lava tube caves.

Devils Postpile National Monument
Devils Postpile
National Monument
Madera County, California
Devils Postpile National Monument
protects and preserves the Devils Postpile formation. The formation is a rare sight in the geologic
world and ranks as one of the world’s finest examples of columnar basalt. Its columns tower sixty feet high and display
an unusual symmetry.

Pinnacles National
Monument
Pinnacles National
Monument is named for a geologic feature – the eroded remains of an extinct
volcano.

San Andreas Fault
San Andreas Fault
California
Named by geologist A.C. Lawson in 1895 for San
Andreas Lake, a "sag pond," on the fault trace about 20 miles south
of San Francisco (now occupied by one of two reservoirs that are major water
storage areas for San Francisco), the San Andreas Fault is the most-studied
fault in the world. Two major
earthquakes have occurred along the San Andreas Fault in recorded history – the
1857 Fort Tejon earthquake and the 1906 San Francisco earthquake. The fault, which is about 700 miles long
extending from Imperial County in southern California northwest to an area of
the Pacific Ocean west of the Mendocino County coastline, is the surface
manifestation of the boundary between two tectonic plates of the Earth's crust
– the Pacific Plate and the North American Plate.

Marshall Gold Discovery State Historic Park
Coloma, California
James W.
Marshall discovered gold in 1848 on the South Fork of the American River. The gold discovery and ensuing gold rush led
to a huge migration of people. The gold
discovery site, located in the still visible tailrace of Sutter's sawmill, is
one of the most significant historic sites in the nation.

Old Woman Meteorite
Old Woman Meteorite
Desert Discovery Center – Barstow, California
The Old Woman Meteorite, which weighed just
over 6,000 pounds, is the second largest meteorite discovered in the United
States. The meteorite was found in 1975
on federal public lands in the Old Woman Mountains in the Needles Resource Area
of San Bernardino County, California.

Subway Cave
Subway Cave
Lassen National Forest – Hat Creek Ranger District
Located near the town of Old Station, the
Subway Cave lava tube, which formed about 20,000 years ago, is about 1,300 feet
long with a height of six to seventeen feet.
Rockhounding Sites for Children & Families
Federal Public Lands
Bureau of Land Management – Barstow
Field Office
The BLM
has identified several areas for recreational rockhounding on BLM-managed
federal public lands. Subject to federal
restrictions, these sites allow recreational rockhounders to collect a variety
of specimens including, agate, azurite, borax, calcite, chalcedony, geodes,
jasper, lava, olivine, opal, onyx, petrified wood, pyrite, satin spar,
travertine, turquoise, and volcanic bombs.
Federal Public Lands
Bureau of Land Management – El
Centro Field Office
The BLM
has identified several areas for recreational rockhounding on BLM-managed
federal public lands. Subject to federal
restrictions, the El Centro field office allows recreational rockhounding.
Federal Public Lands
Bureau of Land Management –
Hollister Field Office
The BLM
has identified several areas for recreational rockhounding on BLM-managed
federal public lands. Subject to federal
restrictions, these sites allow recreational rockhounders to collect a variety
of specimens including, petrified wood and invertebrate fossils.
Federal Public Lands
Bureau of Land Management – Needles
Field Office
The BLM
has identified several areas for recreational rockhounding on BLM-managed
federal public lands. Subject to federal
restrictions, these sites allow recreational rockhounders to collect a variety
of specimens including, agate, chalcedony, chrysocolla, dolomite, epidote,
garnet, geodes, gold, hematite, jasper, limestone, magnetite, marble, opalite, serpentine, and fossils (such as trilobites).
Gold
Bureau of Land Management – Mother
Lode Field Office
Subject to
federal restrictions, the BLM allows low impact gold panning.
Gold
Bureau of Land Management – Redding
Field Office
Subject to
federal restrictions, the BLM allows low impact gold panning.

Jalama Beach
Agate & Onyx
Jalama Beach County Park – Lompoc,
California
Agate and
onyx occurs at the beach.

Benitoite specimen from Benitoite Gem Mine.
Benitoite
Benitoite Gem Mine – Northwest of Coalinga,
California
Commercial (fee access
business). Benitoite is the California
state gem. The rare gem, however, occurs
in very few localities. The business
allows rockhounders to collect specimens on weekends.
Jade
Jade Cove, California
Jade
occurs at the central California coast including Jade Cove. Local beachcombers routinely search for jade pebbles, cobbles, and boulders.
Moonstones
Moonstone Beach – Cambria,
California
The
‘moonstones’ here are different than the gemstone. These are cloudy, milky quartz that display
well when polished.

That's mom and me - looking for obsidian in summer 2011.
Obsidian
Davis Creek, California
Davis
Creek/Lassen in northeastern California is the premier obsidian collecting site
in California. The site is well known
for a variety of obsidian including ‘obsidian needles.’

I'm screening material to find tourmaline in winter 2011.
Pegmatite – Tourmaline
Himalaya Tourmaline Mine – San
Diego County, California
Commercial
(fee access business). The business
allows rockhounders to collect specimens from Himalaya Mine material. The Himalaya Mine is a well known pegmatite
locality famous for gem grade tourmaline. The
Himalaya Mine is one of several commercial mines located in the famed Pala gem
mining district in Southern California.
The area, which has been mined for over a century, is famous for its pegmatite
minerals including quartz, feldspar, mica, beryl, aquamarine, tourmaline, and kunzite
.