Rockhounding near Delta, Utah for Topaz, Mahogany Obsidian & Sunstone

A Rolling Rockhound Review

• Click here to jump to Rockhounding Rules in Millard County, Utah
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• Click here to jump to Mahogany Obsidian at Black Rock Desert
• Click here to jump to Sunstone Knoll
• Click here to jump to Summary Details

Delta, Utah

We came across Delta, Utah, on our way to the Black Hills, South Dakota, from west-central Nevada.  I had never heard of the town, but we’d been dry camping throughout Utah and needed to refresh ourselves and our supplies.  We made an unplanned stop at Antelope Valley RV Park just inside the western limits of Delta.

Delta is a farming community in west-central Utah. It is 150 miles east of Ely, Nevada, and 130 miles south of Salt Lake City, Utah.

It turns out that Delta, in Millard County, is in the very midst of rockhounding country.  Within approximately a 50 mile radius, there are opportunities to find Obsidian, Sunstone, Topaz, Trilobite, Garnet, Placer Gold, etc.  Within a 100 mile radius, there are rockhounding sites for Crystals, Fossils, Dugway Geodes, and more. 

If only we’d had more time! But hey, yah gotta leave something for next time!

Where we Camped

Antelope Valley RV Park fit our needs perfectly with full hookups, a laundry, and a site on the park’s outside edge beneath a big shady tree with an unobstructed view. We were in site #30 for $36 a night with a Good Sam discount.  Their free WIFI had a strong signal, but our AT&T service was light at 2 bars LTE.  It was relatively quiet for bordering Highway 50.

Millard County publishes an excellent Guidebook – get your copy here!

Millard County puts out an excellent tourist guide, describing all of the area’s attractions, including rockhounding.  It has a map dedicated just to rockhounding sites!  You can find the Millard County Tourist Guide for 2020-2021 by clicking here.

Rockhounding Rules in Millard County

The county guide provides the local rockhounding rules for BLM and Utah School Trust Lands, which I have added and expanded upon here:

Additional information

Additional information regarding the rules and regulations for collecting rocks, minerals, and fossils in Utah can be found on the Utah Geological Surveys website by clicking here.

Unfortunately, our time in Delta was limited, having only a couple of days to absorb all we could.  Once again, we found ourselves in an area rich with ATV trails, without an ATV.  That being said, the rockhounding sites we visited were all accessible by 2 wheel drive vehicles.

Rockhounding – Topaz Mountain, Delta, Utah

On our first day in Delta, we headed northwest from Delta to Topaz Mountain via Google maps here:

Topaz, Red Beryl, Apache Tears, Bixbyite, Hematite, Chalcedony, and Amethyst are all found in the Topaz Mountain area.  Topaz is Utah’s state gem occurring as hard, transparent crystals in various colors.  The Utah Topaz crystals occurring at Topaz Mountain are naturally amber colored, becoming colorless upon exposure to sunlight. 

Getting There

Following Google Maps directions, the drive takes about an hour from central Delta.

Take your time and enjoy the barren desert landscape.  There was little to no traffic on the Brush Highway.  It seems as if you are alone in the world out there.  Which also means to be prepared!  Be sure to have plenty of gas and drinking water, and let someone know where you will be. 

We each carry an inReach Explorer (handheld GPS satelite tracking device with SOS capabilities) in case of emergency and to keep in contact if seperated.  Communication with one of these devices certainly isn’t as simple or instant as it woud be using walkie talkies, but it is more reliable.  Our inReach devices utilize satellite allowing us to send simple text messages and share our location. 

There is a BLM sign for Topaz Mountain at Brush Highway and Topaz Road.  Turn north onto Topaz Rd. at the sign.

After turning on to and traveling out Topaz Road, you’ll find dirt roads leading in all directions.  Use Google Maps to get you to the general area.  There are many signs along the way for “Topaz Mountain Adventures,” a “pay to mine,” privately owned quarry. Just follow their signs, bypassing their facility and continuing to the end of the road. There is ample parking amongst the junipers. 

If you would like to increase your chances of finding a Topaz or Bixbyite specimen and don’t mind paying someone to do so, you can make arrangements to visit their quarry.  You can find out more by clicking here for the website, Topaz Mountain Adventures. 

There it is! finding the topaz crystals

Research indicated that searching the washes, perimeter, and slopes of Topaz Mountain may yield small specimens of Topaz and other minerals that have been chipped loose by others or washed loose by rain. You can find some material simply through surface collection alone; however, you’ll probably get better results if you are willing to find a promising seam in the rhyolite and hammer away. Rhyolite is a light gray to pink colored volcanic rock formed during violent volcanic eruptions. The Topaz crystals form in rhyolite seams.

I have a hammer/pick purchased specifically for rockhounding, but I find it difficult to use.  Maybe it is my “leave no trace” hiking ethic or a desire not to disrupt the quiet solitude I often find myself in when rockhounding.  For whatever reason, I hunt the surface more often than I dig or strike rock with a tool. 

Mr. RR, Max, Lola, and I scoured the hillsides and washes on the southwestern slopes of Topaz Mountain.  We came away with a handful of small specimens that we spotted glinting in the midday sun.  I look forward to returning with more time to explore the area, expanding our search to more remote locations around the mountain, and breaking out the hammer.

rockhounding – Black Rock Desert Obsidian

On our second and final day in Millard County, we went in search of Mahogany Obsidian and whatever diversions might strike our fancy.  I had a list of GPS coordinates claiming to lead to strikingly unique varieties of obsidian.  Having spent some time in Lassen, Shasta, and Siskiyou counties, California, I was familiar with obsidian. However, not yet addicted to rockhounding and the lapidary uses of various materials, I wasn’t too impressed with  obsidian… until I discovered Mahogany Obsidian! 

Using the combination of the Millard County guidebook, several sets of GPS coordinates, numerous Rockhounding Guides, Gaia Maps and Google Maps, we started out heading south, fleeing a developing thunderstorm to the north.  A boiling bank of dark dusky black clouds seemed to be tracking us, sticking to our flank as we traveled out of town. As we turned east- northeast into a landscape of rolling foothills spattered in juniper and sage, it appeared we might collide with the angry storm.  As the Rolling Rock tribe’s navigator, it isn’t only my job to get us from point A to point B but also to do so safely.  The weather had me a wee bit concerned, but my rockhounding sense whispered to me that a bit of rain was nothing to fear; besides, we had 4 wheel drive (in the middle of nowhere)!  

Driving to the first set of coordinates we found ourselves driving on a road littered in grains of black obsidian. After parking, we hopped out of the truck to find ourselves enveloped in a foggy mist.  We fanned out and searched the area finding Apache tears and small pebble sized pieces of obsidian, some with dull red streaks in them.  Excited that we’d found the coordinates and some obsidian, we filled our pockets.

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However, I had another set of coordinates, and the storm had passed.  We proceeded on to the next set of GPS coordinates and after a few wrong turns, came upon a mahogany obsidian pit. There was obsidian everywhere, and it ranged in size from a small pebble to 6 inches and more!  The quarry is considered a community pit where you are allowed to collect up to 250 lbs. a year for personal use.

The piles of rock surrounding the pit were a mix of Snowflake, Black and Mahogany Obsidian. Most of it was black with streaks and ribbons of mahogany, gold and even olive green in it.  Some of it had a bit of glittery gold-like material in it as well.   Mr. RR quickly reminded me that we live in an RV and are already close to our truck’s weight hauling limits.  Wow! There was so much obsidian in every shape and size. We wandered the area collecting, handling, and just absorbing the beauty and abundance of it all.

Mahogany Obsidian is a black volcanic glass-like stone with swirls of reddish-brown resembling mahogany wood grain.  The reddish-brown coloring is caused by iron or hematite inclusions.  I have since begun shaping it with my Dremel and find it easy and fun to work with.

Directions

I believe these are the GPS coordinates for the community pit, 38°47’01.0″N 112°49’49.5″W.

From the west edge of Delta, Utah, travel west on U.S. Highway 6/50 about 4.3 miles to the State Highway 257 junction. Turn south on highway 257 and travel approximately 43 miles to a BLM sign displaying “Kanosh 26” and a dirt road heading east. Once on this dirt road travel approx 2.5 miles to the first location. To get to the second site, drive another 4.5 miles east to the top of the pass, turn right on a dirt road leading to the quarry. This dirt road travels up hill to the parking area.

Remember to take only what you can personally use.

Pahvant Valley Heritage Trail

Utilizing Gaia Maps and the Millard County guide to find our way, we headed to the Pahvant Valley Heritage Trail. We didn’t have time to drive the whole trail – we’ll have to save that for next time. We thought we’d at least stick with the rock theme and check out some petroglyphs.

Click here for a link to the BLM Map.

Hole in the Rock

We came upon a spot on the road with a small sign and what looked like a trailhead.  The sign simply said “Hole in the Rock”.  It was difficult to find any information on what it was all about.  It turned out to be a petroglyph site.  The petroglyphs are scattered about on the rocks beneath the small ridge.  Walk through the fence at what appears to be a trailhead and walk down hill and around the bottom of the small rocky ridge.  Look up at the rocks supporting the ridge and you’ll find some faded petroglyphs.  Take some time to hike up, around and on top of the ridge for distant views of wide open country.  You may see a Pronghorn or two.

Devil’s Kitchen Petroglyphs

Utilizing all of the navigating source mentioned previously, we made our way to the Devil’s Kitchen Petroglyphs.  The road comes to a parking area clearly signed for the Devil’s Garden Petroglyphs with a trail leading through a break in the fence.  The petroglyphs here are much more numerous, again on the rocks supporting the ridge above you. 

Rockhounding – Sunstone Knoll

Previewing our route home, we noticed that it took us past Sunstone Knoll. Sunset Knoll is a prominent feature along Highway 257 just south of Delta. 

There you can collect sunstones.  Sunstones are transparent yellowish labrodite crystals.  There are two ways of collecting the crystals.  One is by hammering and chipping away at the rock on the top of the small knoll and the other is by surface collection on the flats surrounding the knoll.

It had been a long day but it was on the way back to camp. Now, how could we not stop?   I initially tried a little hammering unsuccessfully, so I headed out to the flats.  There I found many small specimens.  Just look for their sparkle in the sunlight.

Summary

• Topaz Mountain
  • GPS Coordinates: 39.7094° N, 113.1033° W
  • Google Maps: Click here for Google Maps link
  • Minerals present: Topaz, Red Beryl, Apache Tears, Bixbyite, Hematite, Chalcedony, and Amethyst
  • Method: Surface and/or Hammer/chisel
  • Jurisdiction: BLM & Private Claims,
• Black Rock Desert Obsidian
  • GPS Coordinates: 38°47’01.0″N 112°49’49.5″W
  • Google Maps: Click here for Google Maps link
  • Minerals present: Obsidian – Mahogany, Snowflake, Black & Apache Tears
  • Method: Surface Collection
  • Jurisdiction: BLM, State Trust Lands & Private Claims
• Sunstone Knoll
  • GPS Coordinates: 39.1463478°N, -112.7171718°W
  • Google Maps: Click here for Google Maps link
  • Minerals present: Labrodite “Sunstones”
  • Method: Surface and Hammer/chisel
  • Jurisdiction: BLM and private claim
  • Safety: Watch for train when crossing tracks and beware of rattlesnakes and broken glass
• Road classifications – 2x, 4x, UTV, or Foot: All three sites can be reached by 2 wheel drive on paved and dirt roads. Topaz Mountain and the Black Rock Desert are fairly remote areas so be prepared.
• Hike Classification (Difficult, Moderate, a stroll in the park): Accessing these sites from your vehicle is mostly a stroll in the park.  Its all up to you.
• Hike Distance: All of these sites can be driven up to.  Walking distance is negligible.
• Environment (Desert, Forest, etc.): Desert, scrublands and foothill.
• Safety concerns: Typical of a desert environment; watch out for poisonous creatures & predators, carry a safety tracking tool and paper map, always tell someone where you are going and do not go alone, take plenty of water, be sure your vehicle has plenty of fuel and check your tires before heading out.
• Where we stayed: Antelope Valley RV Resort
• Camping nearby:
  • Antelope Valley RV Resort, Delta, Utah
  • Millard County Campground list
  • Check with the local Chamber of Commerce regarding additional RV Campgrounds & Resorts in the area.
• Boondocking nearby: 
  • BLM – Boondocking can be done on BLM lands near each site. Check with the local BLM office for current rules and regulations at (435) 743-3100
  • Utah State Trust Lands – Boondocking is allowed on most State Trust lands in Utah for up to 15 days. For more information click here.
• Resources:
  • Utah Geological Survey – Sunstone Knoll
  • Utah Geological Survey – Obsidian in the Black Rock Desert
  • Utah Geological Survey – Topaz Mountain
  • BLM – Topaz Mountain