
Rockhounding Montana
Montana is an extraordinary state for rockhounding. The state – known as the ‘Treasure State’ – is well known for its enormous copper (the 'richest hill on earth') and coal deposits as well as an 1800s gold rush. In addition, the state is famous for its sapphires and its agates. Today, however, the state is world-renown for its dinosaur fossil sites. It also is home to some very unusual ringing rocks. I enjoy rockhounding in Montana ... and visiting my grandparents … even though I was nearly hit by lightning. Really!
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.

Montana Agate (cut and polished)

Sapphires that I found in Montana.
State Gemstones: Montana Agate & Sapphire (1969)
Montana designated both the Montana agate and sapphire as its two official state gemstones in 1969. Montana is well known for its ‘Montana agates’ (or ‘moss agates’) that can be found in the gravel beds of the Yellowstone River in southeastern Montana. ‘Moss’ refers to the dendritic patterns that may occur in the agates as moss-shaped inclusions, resulting from the presence of manganese or iron oxides.
In addition, Montana also is well known for its sapphires. Sapphire is a variety of corundum. Red corundum is called ruby while all other colors are called sapphire. Sapphire is found as an accessory mineral in metamorphic rocks. In 1865, the first U.S. sapphires were found in the gravels of the Missouri River in Lewis and Clark County, Montana. This was followed by subsequent discoveries on Dry Cottonwood Creek in Deer Lodge County in 1889, on Rock Creek in Granite County in 1892, and in Yogo Gulch in Judith Basin County in 1895. Small amounts of sapphire also are recovered from Quartz Gulch in Granite County, Pole Creek in Madison County, the Missouri River in Chouteau County, and Brown's Gulch in Silver Bow County. In addition, corundum crystals, from which star sapphires have been cut, are found in Beaverhead and Madison Counties.

Maiasaura Peeblesorum
State Fossil: Maiasaura Peeblesorum (1985)
Montana designated the duck-billed
dinosaur Maiasaura peeblesorum as its official state fossil in 1985. Maiasaura peeblesorum lived on the coastal plains and lowlands along the
Cretaceous Interior Seaway about 80 – 70 million years ago. Fossil localities have yielded multiple nests
and the remains of over 10,000 individuals, suggesting that these hadrosaurs
lived and cared for their young in herds. Maiasaura
are in the "hadrosaurs" family.
All hadrosaurs were medium-sized, bipedal, herbivorous dinosaurs of the
Upper Cretaceous Period with long flat snouts and a crested skull. They also had three toes on the hind feet and
four toes on the front. An adult
Maiasaura was nearly thirty feet long, weighed about three tons, and had a tiny
knob between its eyes. The dinosaur
walked on its hind legs, with its tail held out straight for balance. When newly hatched, the duck-billed dinosaur
was less than fourteen inches long and weighed about one and a half
pounds. Adults grew to over thirty feet
in length and weighed three tons. One of the most significant paleontological discoveries of the latter 20th
century came in 1978, when fossils of a nesting colony of duck-billed dinosaurs
were found west of Choteau, Montana (now known as ‘Egg Mountain’). The
findings at Egg Mountain provided valuable evidence that Maiasaura nested in
extensive colonies and had nests six feet in diameter with as many as twenty
eggs. The nest was seven feet wide and
two and one half feet deep, and shaped like a bowl. It's believed the young may have remained in
the nest for up to two months. This
demonstrated for the first time parental care of dinosaur young. Paleontologist
Jack Horner and research partner Bob Makela determined that the species, which
they named Maiasaura (“good mother lizard”), raised its young in colonies, as
many birds do, rather than abandon the nest after laying eggs, like reptiles. The
second part of its scientific name, peeblesorum, honors the Peebles, a Montana
ranch family from the Choteau area where the discoveries were made.
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!

Montana Bureau of
Mines & Geology
Functions, in part, as the state’s geological
survey.

US. Bureau of Land
Management – Montana/Dakotas
Office
publishes - Rock Hounding On Public Land In Western Montana (Rev.
8/06) an informative six-page
guide regarding rockhounding on federal lands managed by the BLM.

U.S. Forest Service
The Forest Service manages enormous amounts of
federal public lands in Montana. Subject
to federal restrictions (and district restrictions), portions of some of the
National Forests in Montana are open to recreational rockhounding. The USFS publishes a useful overview.

The Montana
Dinosaur Trail
Includes information on several Montana
museums with dinosaur and fossil collections.
- David D. Alt & Donald W. Hyndman, Roadside Geology of Montana (1986)
- Montana Hodges & Robert Feldman, Rockhounding Montana (2d ed. 2006).
- Robert Feldman, The Rockhound’s Guide to Montana (1985).
- Lanny R. Ream, The Gem, Mineral, & Fossil Collector’s Guide to Montana (1992).
- Jack Horner, Dinosaurs Under the Big Sky (2001).
- H.C. Dake, Northwest Gem Trails (2d ed., 1956 – originally published in 1950).
- Allan W. Eckert, Earth Treasures Vol. 3 - Northwestern Quadrant (1986; reprint in 2000)
- James Martin Monaco & Jeannette Hathway Monaco, Fee Mining & Rockhounding Adventures in the West (2d ed. 2007)
- Kathy J. Rygle and Stephen F. Pedersen, Northwest Treasure Hunter's Gem & Mineral Guide (4th ed. 2008)
Museums of Interest to Rockhounders

The Sign was bigger than me, but the dinosaurs were enormous
Museum of the
Rockies
Montana State University – Bozeman, Montana
Showcases one of the largest and most
important dinosaur collections in the world. The museum is known for its paleontological collection. Based on the
research of paleontologist and advisor to the Jurassic Park films, Dr. Jack
Horner, the Museum features T. Rex, Triceratops, Torosaurus, and more. The museum houses the most T.rex specimens anywhere in the world -
currently 13.

Me with the T. Rex skull at the Museum of the Rockies
Mineral Museum
Montana Tech - Montana Bureau of Mines & Geology - Butte, Montana
The Mineral Museum overlooks the 100-year
old Butte Mining District. Includes
classic mineral specimens from Butte's underground mines, which include over
3,000 miles of mine workings that reach over a mile deep. The museum's collection has over 15,000
specimens from worldwide localities, and 1,300 spectacular minerals from
the Butte mines, including a 400-pound smoky quartz crystal.

University of Montana Paleontology Center
University of Montana – Missoula, Montana
The UMPC collection contains an estimated
100,000 specimens with over 1,500 representing type (published) specimens. Displays featuring some of the UMPC holdings
are located on the first and third floors of the Charles H. Clapp Building.
World Museum of Mining
Butte, Montana
The museum’s mineral room exhibits local rock
and mineral specimens.
Two Medicine Dinosaur Center
Bynum, Montana
The Two Medicine Dinosaur Center houses a wide variety of dinosaur species,
invertebrates, plant fossils, archeological materials, and cultural items. Also on display are some of Montana's rarest
fossil discoveries. One such is a
display of the first infant Maiasaura bones from the famous Egg Mountain area.


Phillips County Museum
Phillips County Museum
Malta, Montana
Seventy million years ago, that area that would
become Phillips County, Montana was a shoreline along a massive inland
sea. As a result, this area of Montana
is includes numerous fossil deposits. The museum exhibits several fossils
excavated from the Judith River Formation, including a complete 33-foot-long Brachylophosaurus
skeleton as well as an Albertosaurus and many locally discovered fossils.

Rudyard Historical Society Dinosaur Museum
Rudyard, Montana
This small museum exhibits dinosaur fossils
including Maiasaura, Troodon, Tarasaurus, and Rudyard’s own Gryposaurus. The museum collaborates with the Museum of
the Rockies to rotate exhibits.

Torosaurus skull
Central Montana Museum
Lewiston, Montana
The museum exhibits rocks, minerals, gems, and
fossils. The museum also includes a
full-scale replica of a Torosaurus dinosaur skull that was found in the
Valentine area (about 65 miles east-northeast of Lewistown).
Earth Science Museum
Northeast of Fort Benton in Loma, Montana
The museum exhibits local rocks, minerals,
gems, and fossils.
Places to Visit - Interesting Sites To See

My cousin Alex and me in 2012.

Alex and me at Avalanche Lake in Glacier National Park.
Glacier National
Park
Northwestern Montana
Glacier National Park includes glaciers,
glacially carved mountains, and Precambrian era rock formations. In addition, the Park includes some of the
oldest fossils in the world (stromatolites
occur in the 1.5 billion year old limestone and dolomite in the Altyn
Formation).

My cousin Alex and me in 2009.

I took this photograpgh of Old Faithful.
Yellowstone
National Park
Southern Montana (as well as Idaho & Wyoming)
A small portion of America’s First National
Park – Yellowstone National Park – extends into Montana. Yellowstone, of course, is amazing. Visitors can see fossilized trees, geysers, hot springs, bubbling mudpots, steaming fumaroles, travertine formations, and obsidian cliffs – all within
an ancient, but still active, giant volcanic caldera. Yellowstone National Park is home to one half
of the world’s geothermal features. Its more than 300 geysers make up two thirds of all
those found on earth.


Pompey's Pillar
National Monument
About 25 miles East of Billings, Montana - The Pillar
overlooks the Yellowstone River
Pompey's Pillar is one of the most famous
sandstone buttes in America. It bears
the only remaining physical evidence of the historic and courageous Lewis and
Clark Expedition, which appears on the trail today as it did over 200 years
ago. On the face of the 150-foot butte,
Captain William Clark carved his name on July 25, 1806, during his return to
the United States through the beautiful Yellowstone Valley. Captain Clark
named the pillar "Pompey's Tower" in honor of Sacagawea's son Jean
Baptiste Charbonneau, whom he had nicknamed "Pomp." Nicholas Biddle, first editor of Lewis and
Clark's journals, changed the name to "Pompey's Pillar."

Berkeley Pit Copper Mine - Richest Hole on Earth
Butte, Montana
Enormous former open-pit copper mine
approximately one mile long and a half-mile wide. The pit is over 1,700 feet deep.

Montana Dinosaur Trail
Montana
Statewide information about Montana sites and
museums regarding local dinosaur sites.

Ringing Rocks Pluton
Between Butte and Whitehall, Montana
Montana’s unusual ‘Ringing Rocks’ formation is
located in the Deerlodge National Forest (managed by the BLM), approximately
20 miles east of Butte, Montana in the Rocky Mountains [Exit 241 (Pipestone)
from Interstate 90]. The Ringing Rocks
ring like a bell when lightly hit with a hammer. The Ringing
Rocks are a very small part (about 160 acres) of a mountainous region called the
Boulder Batholith, which encompasses a large portion of southwestern Montana. Batholiths originate when magma cools slowly
beneath the surface to form granite. Following uplifting and erosion, the granite is exposed. Pennsylvania also has ringing rocks.

Lewis & Clark
Caverns State Park
Between Bozeman and Butte, Montana
Montana's first and best-known state
park showcases one of the most highly decorated limestone caverns in the
Northwest. Naturally air conditioned, these
spectacular caves are lined with stalactites, stalagmites, columns, and
helictites.

Tom Miner Basin Petrified Forest
Gallatin National Forest – North of Yellowstone
National Park
The Tom Miner Basin, which is federal public lands
managed by the United States Forest Service, contains a petrified forest. The Eocene era petrified forest is between 55
and 35 million years old. The site is
unique because many of the fossilized trees are vertical. There is an interpretive trail. The specimens are interesting to see.

Earthquake Damage
Earthquake Lake Visitors Center – West of Yellowstone
National Park
The Madison River Canyon Earthquake Area is the
site of a significant and devastating earthquake in 1959 (28 people were
killed). The earthquake measured 7.5 on
the Richter scale (the largest recorded earthquake in the United States at the
time) and sent eighty million tons of mountain into the Madison River. The US Forest Service’s Earthquake Lake
Visitors Center is located approximately 25 miles from West Yellowstone,
Montana.

Granite Ghost Town, 2007.
Granite Ghost Town
Granite County, Montana
Several historic ghost towns are located in Granite
County Montana. The Granite County
Museum located in Philipsburg, Montana is home to the Montana Ghost Town Hall
of Fame. Nearby, the Philipsburg area is home to several ghost towns including Granite, which
was nicknamed ‘Montana’s Silver Queen.’
The ghost town of granite is located on Granite Mountain four miles east
of Philipsburg.
Rockhounding Sites for Children & Families

Quartz Crystals,
Amethyst, Smoky Quartz
Crystal Park - Beaverhead-Deerlodge
National Forest
The Crystal Park
site is under claim to the Butte Mineral and Gem Club and is jointly maintained
and supervised by the club and the Beaverhead National Forrest. The site is located 7,700 feet above sea
level in the Pioneer Mountains of the upper Big Hole Valley southwest of Butte,
Montana in the Beaverhead-Deerlodge National Forest.
This site has been
a favorite with recreational rockhounds for decades because of the
exceptionally well-formed quartz and amethyst scepter crystals. Lucky rockhounds also might find a
"Japan Law Twin,'' a pair of crystals joined at an unvarying angle of 84
degrees, 39 minutes. Another prize is a "scepter,'' a larger crystal
on the end of a smaller one. The Butte
Mineral and Gem Club began filing mineral rights claims at the area in the late
1950s. In 1976, the group entered into a
cooperative agreement with the Forest Service for the management and
development of Crystal Park for public recreation. The club contributed funds for a boundary
fence and portable toilets. Crystal Park is about 65 miles SW of
Butte. From Butte, take Interstate 15 south about 25 miles to the exit to
Divide. Take MT 43 about 11 miles to the town of Wise River. At
Wise River, take the Pioneer Mountains Scenic Byway Road approximately 25 miles
to Crystal Park.

Petrified Wood
Gallatin National Forest – North of Yellowstone
National Park
The Tom Miner Basin, which is federal public
lands managed by the United States Forest Service, contains a petrified
forest. The specimens are interesting to
see. Subject to federal restrictions and
obtaining a permit (in advance), individuals are allowed to collect a single
twenty cubic inch specimen (about fist sized).
Sadly, of course, people abuse the site.

Grandpa, Grandma, and me in 2007.
Sapphires
Gem Mountain Sapphire Mine - Near Phillipsburg, Montana
Commercial (fee access) business. Visitors can screen gravels from the famed Rock Creek Sapphire site. These are pictures from 2007 when we took my grandparents to look for sapphires to celebrate their 45th wedding anniversary (the sapphire anniversary).

Me and mom - screening for sapphires. I'm six, but with a 'hawkeye' for spotting sapphires.

Here, I'm beating dad to finding the sapphires. I did that all day. A sharp eye and quick fingers.

Now, I'm spottig the sapphires with grandpa and grandma.

Sapphires
Spokane Bar
Sapphire Mine & Gold Fever Rock Shop
Helena, Montana
Commercial (fee
access) business. Visitors can screen gravels from Missouri River gravel
terraces. The geologic structure called
Spokane Gravel Bar is a deposit consisting of unsolidified sediments, deposited
by an ancient river. The site is located near
Hauser Lake along the Missouri River (near Helena, Montana). Discovered in the early 20th century by
geologists mapping the Missouri River area, the site was named after the Spokane Hills
that are composed of Spokane shale. The
present river level is more than 50m below the ancient river deposits. Four major gravel terraces are visible on both
sides of the river.
Montana Agates
Yellowstone River, Montana
‘Montana
agate’ or ‘Montana moss agate’ specimens may be found along the Yellowstone
River’s extensive route through Montana.
Although many collectors favor sites near the North Dakota border, I’ve
found agates just outside Yellowstone National Park at the opposite end of the
river.

Limonite cubes that I found.
Limonite Cubes -
Pyrite Psuedomorphs
Cooper Lake – NE of
Helena, Montana
This site is located within the Helena
National Forest. Limonite has replaced
the pyrite cubes forming fascinating psuedomorphs. Most are less than one-half inch, but
occasionally as large as two inches.
Limonite Cubes - Pyrite Psuedomorphs
Northwest Montana
Limonite has replaced the pyrite cubes forming fascinating psuedomorphs. The matrix rock is the billion-year-old Belt Formation. I visited the site in 2009. A thunderstorm rolled in and my grandpa, dad, and I had to wait it out inside a small cave, as the lightning was right on top of us. My hair stood on end … but, I found some terrific specimens.

Limonite cube in the matrix. This rock is about one billion (with a 'B') years old.

At last - the specimen is liberated.

Notice the cubic shape of this extraordinary specimen.
Picture Jasper
Montana City, Montana
Exit 187 off of Interstate 15 - Road
cut on NW side of interchange
Calcite Crystals
Drummond, Montana
Calcite crystals (and rattlesnakes) can
be found in the Rattler and Spring Gulch areas approximately 4 to 5 miles
northwest of Drummond. In 2008, while visiting the area, I found both.
Smoky Quartz Crystals – ‘Montana
Diamonds’
Judith Peak – North of Lewistown, Montana
Doubly terminated smoky quartz crystals can be found near
the top of Judith Peak, north of Lewistown, Montana on federal public lands
managed by the BLM in Fergus County. The small crystals –
sometimes called ‘Montana Diamonds’ – weather from porphyritic rock.