
Rockhounding North Dakota
North Dakota is a good state for rockhounding.
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.

Teredo Petrified Wood
State Fossil: Teredo Petrified Wood (1967)
North Dakota
designated Teredo petrified wood as its official state fossil in 1967. The fossilized wood bears the boreholes of
shipworms, genus Teredo, hence its name. Shipworms are actually a type of mollusk (not
worms at all) that were the bane of mariners past and still wreak havoc today
on wooden boats and dock posts. During
the Paleocene Epoch, about 60 million years ago, North Dakota was partially
covered by the last seaway to invade North America, the Cannonball Sea. The swamps and lowlands bordering this sea –
not too different from Florida today – were home to enormous crocodiles and
giant predatory birds. The marine fauna
includes bony fish and sharks, crabs, lobsters, snails, and clams. Trees that washed into the sea were frequently
attacked by shipworms before they were fossilized, leaving them riddled with
holes. As the trees in the mineral rich
water petrified, some of the wood was replaced by silica and quartz, thereby
preserving evidence of the Teredo. This
wood belongs to a variety of species, including bald cypress, ginkgo, redwood,
and magnolia trees. Teredo petrified
wood is one of the most common North Dakota fossils and is known almost
exclusively from the Cannonball Formation in Morton County, North Dakota. The best collecting sites are in the
south-central portion of the state.
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!

North Dakota Geological Survey
The North Dakota
Geological Survey has information about local rocks and minerals. In addition, one of the great – and unusual –
programs of the North Dakota Geological Survey is its Paleontology Fossil Digs
Program. This program allows members of
the public to participate in an expert-led fossil dig.

U.S. Bureau of Land Management – North Dakota Office
- June Culp Zeitner, Midwest Gem, Fossil, & Mineral Trails: Prairie States (Rev. ed., May 1998 – first published in 1955).
- June Culp Zeitner, Midwest Gem Trails: Field Guide for the Gem Hunter, the Mineral Collector, and the Tourist (3d. Rev. ed., 1964 – originally published in 1956).
- 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 & Stephen F. Pedersen, Northwest Treasure Hunter's Gem & Mineral Guide (4th ed. 2008).
Museums of Interest to Rockhounders

North Dakota Heritage Center (state museum)
State Capitol – Bismarck, North Dakota
The North Dakota Heritage Center houses the
state’s fossil, rock, and mineral collections.

Dakota Dinosaur Museum
Dickinson, North Dakota
The museum is proud of their Triceratops skeleton and skull that is in excellent shape
and recent acquisitions include a baby Tyrannosaurus Rex. Most of the exhibits are real and many of
them were found locally. The museum also
has a fluorescent mineral display containing many different types of stones and
minerals. The museum has over 800
different specimens of rocks, seashells, minerals, and invertebrate fossils as
well as vertebrate fossils of animals other than dinosaurs.

Broste Rock Museum
Broste Rock Museum
Parshall, North Dakota
The museum, constructed of local field stone, exhibits
specimens from all over the world including rocks, minerals, fossils, and
meteorites.
Places to Visit - Interesting Sites To See

Cannonball concretions at Theodore Roosevelt National Park
Theodore Roosevelt National Park
Southwestern North Dakota
The Theodore Roosevelt
National Park is located in the Badlands.
The park contains numerous fossils (including petrified wood) as well as
interesting geologic formations. The
best known petrified forest in North Dakota is found in the South Unit of
Theodore Roosevelt National Park. There,
coniferous stumps from two successive forests have eroded out of the Sentinel
Butte Formation. These trees are related
to the modern Sequoia; some
stumps are up to twelve feet in diameter. The stumps are still upright in the place
where they grew fifty-five million years ago in a coastal floodplain
environment. The stumps were preserved
as floods inundated the forest floor, burying the bases of trees; the unburied
trunks and branches simply decayed away.

North Dakota State Capitol Grounds
Bismarck, North Dakota
An eighty-foot long petrified log and two
stumps are displayed on the capitol grounds by the arboretum trail.

Burning Coal Vein
Northwest of Amidon, North Dakota
The Little Missouri National Grasslands in
southwest North Dakota, managed by the United States Forest Service, includes
an underground coal seam that caught fire over one hundred years ago. The coal continues to burn.
Rockhounding Sites for Children & Families
Petrified Wood
Southwestern North Dakota
Petrified
wood is fairly common in southwestern North Dakota. In fact, during construction of Interstate 94 west of
Dickinson, a 120-foot-long, petrified "redwood" log six feet in
diameter was uncovered. The specimen was
offered to nearby towns as a tourist attraction, but was reburied when no one
wanted it.