Over 2 million years ago, Millard County was a volcanic hotspot. Eruptions that occurred in western Utah’s Black Rock Desert helped form a variety of volcanic rocks, including pumice, rhyolite, and, most notably, obsidian — a type of volcanic glass that forms when lava cools quickly and is known for its dark, glassy appearance.
ABOUT THE AREA
While most people know obsidian to be black, it can also range in color from red to brown. Our desert is known to have three common varieties: mahogany, snowflake, and black obsidian. Mahogany obsidian has a distinct red-brown color due to Hematite or Magnetite inclusions, while snowflake obsidian is black with white-gray spots of quartz crystal. This type of obsidian was commonly used in the past to create knives and arrowheads.
Today, rockhounds from far and wide come to Millard County’s obsidian beds around Black Spring and Coyote Spring in the Black Rock Desert, excited by the prospect of our diverse geological landscape as an ideal rockhounding destination for all kinds of rocks, minerals, and fossils. We invite you to spend a day here and see what geological marvels our desert has to offer!
Where to Find Obsidian
GPS COORDINATES:
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38.7694° N, 112.8322° W(BLACK SPRING) |
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38.7789° N, 112.8340° W(OBSIDIAN BED) |
Obsidian can be found west of Black Rock on the hillsides and on the roadbeds near Coyote Spring and Black Spring. To get there:
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Take Highway 257 south from Deseret for about 43 miles until you come to a sign identifying a road that heads east to Kanosh. |
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Turn east onto the dirt road and travel about 6 miles to the sign for Black Spring. |
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Turn right onto the Black Spring dirt road and park in the open area by the watering trough. Obsidian can be found all around that area. Most pieces are black, but some reddish-brown and snowflake obsidian can be found. |
When traveling from Fillmore:
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Take I-15 south to exit 146 south of Kanosh. |
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Cross the freeway to the east and turn south on the first frontage road. |
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Travel south to a bridge crossing the freeway to the west. Follow this gravel road bearing west for approximately 26 miles. |
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Alternatively, you can take Highway 6 & 50 west of Delta to SR 257 and turn south. Continue on for 43 miles past the Graymont lime plant until you reach the BLM sign that says “Kanosh 26.” |
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Turn east and follow the dirt road for 5.25 miles. In the depression, one road goes east, and the other goes north. Mahogany, snowflake, and black obsidian can be found on the hillsides and on the roadbeds near Coyote Spring and Black Spring. |
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Take the north road and then turn east at about 0.25 miles on the first side road going east. |
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Drive up the hill and over the crest to collect obsidian. You can collect your own mahogany obsidian at this community pit. |
What to expect & how to prepare
When you arrive at the destinations described above, you can find obsidian on the ground in any direction you walk. You’ll likely find 0.5- to 6-inch pieces of black obsidian, but you can sometimes find snowflake and mahogany obsidian as well. The area is home to cattle and rattlesnakes — so watch your step!
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What to bring: It may be easier to access rockhounding sites with a four-wheel vehicle, but you should still be able to access them with other vehicle types. Rockhounding tends to be an all-day activity, so bring enough food and water for each person coming with you. You’ll need at least a gallon per person, especially if the weather is expected to be hot. Bring a hammer and protective eyewear so you can break the rock more easily to extract samples — and have a trash bag with you so you can pack all your garbage out. Sunscreen and a hat can also be helpful to protect your eyes and skin from the sun. |
COST
Most state lands are administered by the Schools and Institutional Trust Lands Administration and require a rockhounding permit to collect on these lands. Check their website for current pricing. They allow you to take up to 25 pounds of material daily plus one piece per person or 250 pounds per year.
DOWNLOAD your rockhounding permit here
Rules for collecting on blm lands
Here are the restrictions on what you can take:
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The casual rock hound or collector may take small amounts of fossils, gemstones, and rocks from unrestricted federal lands in Utah without obtaining a special permit if for personal, non-commercial purposes. |
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Petrified wood may be collected for non-commercial use only from public lands — up to 25 pounds plus one piece of any size per day with a yearly limit of 250 pounds. |
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Collection in large quantities or for commercial purposes requires a permit, lease, or license from the BLM. |
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When you remove what you want to take, try not to disturb the surface too much. You may not collect on marked claims. |
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As Utah is home to the ancestral land of eight tribal nations, please show respect by not removing artifacts and obtaining all required permits before extraction. |
Rockhounding Tips & Permit
Learn some expert tips from experienced rockhounds and get your rockhounding permit!
BEST TIME FOR OBSIDIAN ROCKHOUNDING
Most rockhounds consider spring and fall the best times for this activity. Being in the blistering summer sun or trying to extract from the frozen ground can turn a fun, rockhounding adventure into a miserable day. The desert is prone to flash flooding, so be diligent in checking the weather forecast as you plan your trip.
