The southern part of the Black Rock Desert is a nice day trip from Reno and includes a variety of geologic environments, mines, trails and historic sites along with the flora and fauna typical of the Basin and Range. Leaving Reno at 05:30 we drove around the south end of Pyramid Lake and turned north. It was just full light when we passed the tiny community of Empire, five miles south of Gerlach, where a large deposit of gypsum has been mined and processed for decades.

Gerlach means Bruno’s, the only place to eat and one that serves meals definitely not for sissys. It is located at the west end of the Black Rock and is the last outpost of civilization for nearly a hundred miles in any direction.

We breakfasted and then turned south for a few miles to pick up the road along the south edge of the Black Rock. This is a gravel and mud track that parallels the railroad between Gerlach and Winnemucca some 100 miles to the east. The only activity in this area is around the Hycroft Mine at Sulphur, about halfway between the two towns. We proceeded to drive east enjoying stunning views of the Chocolate Mountains, the Black Rock to the north and local points of interest. These included a rather cold pine gopher (bull) snake and the markers indicating the passing of the emigrants along the Applegate Trail in the 1840’s. Tracks are still visible in the alkali at the edges of the Black Rock where wagons passed more than 150 years ago.

Approaching Sulphur the large and colorful waste piles and leach pads of the mining operation are visible from 15 miles away. This property produced gold and silver and then sulphur and aulunite in the past but more recently, since the 1980’s, has produced gold and silver from low-grade ore bodies associated with hydrothermal activity along Basin and Range faulting.

The alteration along the structures has produced a rich range of colors in the rocks that include reds, ocher and stark white with many shades of browns and grays. Current operators are expanding the known ore zones and will resume mining operations in the near future. All ores are processed by heap-leaching, the most efficient method of extracting gold from the low-grade ores. The old town site of Sulphur is adjacent to the railroad tracks about a mile west of the Hycroft Mine. Only a few foundations and building and equipment remnants remain.

This property has produced interesting specimens of sulphur, cinnabar, stibnite, opalized and silicified rocks, calcite and some more uncommon minerals in isolated occurrences. At the north end of the property is an occurrence of silicified reeds near a ‘fossil’ hot spring.

To be continued…

Leaving the Sulphur area we drove a few miles to Rosebud Canyon and the Rabbit Hole Springs. Rosebud Canyon was placered by early prospectors and there is a small, currently inactive underground silver mine (Rosebud Mine) as well.  This mine has produced some excellent specimens of barite and a variety of silver minerals. Again, there are a number of trail markers with information from the journals of travelers in the wagon trains. Rabbit Hole Spring at the west end of the canyon was a welcome stop for the weary emigrants as they prepared to start the trek north across the Black Rock Desert.

Following the path of the emigrant trail from Rabbit Hole Spring to the Gerlach-Winnemucca road we turned west, stopping for a look at an area with reported trilobite fossils.  Directions were vague and we didn’t have time for prospecting so a bit of research will be needed before returning for another try. We hiked around the base of a granite intrusive, checking out some prominent veins of feldspar and quartz. They were barren with no associated openings or loose areas where one might find crystals.

Trego Hot Springs is near the road about 20 miles east of Gerlach. It consists of a series of pools and ‘tanks’ surrounded by cottonwood, willow and tamarisk trees with lush grasses and cattails in the wetter areas. It is truly an oasis in the desert and it attracts wildlife of all kinds. It is a popular spot for campers and bathers; one should be careful to not surprise anyone who has “forgotten” their bathing suit. The source of the warm water here is a series of wells drilled into artisian, geothermally heated groundwaters.                 

The crystal-clear pool pictured is about 85 degrees warm and has an 8 inch pipe in the center running about 20-30 gallons per minute.
The last stop of the day was at a small tungsten prospect high on the mountain overlooking the western Black Rock. The workings are in a fairly thin carbonate unit near the contact with a granite intrusive. The beds are very steeply dipping to overturned and show a typical development of garnet-diopside and marble skarn. There are a few boulders or outcrops showing rather large (to 10 inches) crystal sprays of clinozoisite but they are uncollecteble on the massive, tough blocks of skarn. Garnet is common in the skarn although crystals are indistinct.

As we headed down the trail to our truck we could see rain and snow showers to the north in the Granite Range. A brisk wind and cold sprinkles hurried us along as a train passed headed for the West Coast.

The Leadville Mine northeast of Gerlach in Washoe County, Nevada, has produced a variety of metals from ores associated with porphyritic dikes in andesite. There is a mention in the literature that there were large fluorite crystals associated with the deposits, although there are no real details describing the occurance. It was worth a trip to see this area and some new country and to check out some geode areas on the north side of the Blackrock.

We left Reno early and had breakfast at Bruno’s in Gerlach, the iconic restaurant on the Black Rock-Smoke Creek junction. We traveled by paved and then gravel roads about 35 miles NE to the turn into the Leadville District. A good jeep trail leads to the mine site. It was a very windy and cold day with showers at the 6,000 plus foot elevation, but the flowers were out and a lone antelope and several groups of mustangs didn’t seem to mind the weather. We spent several hours climbing over mine dumps and looking at prospect pits on the main structure and to the southeast on several parallel dikes. The dumps produced several specimens of massive galena, one of sphalerite and numerous samples of sulfide-rich waste rock. There was no recognizable fluorite on the dumps or on the mineralized structure on a single exposure on the drainage south of the main workings.

We left Leadville and drove north to check an area where Sam Knipmeyer, my digging partner, had prospected with his dad in the 80’s. There is a nice display of petrified logs next to the road, protected from passing rock hammers by a sturdy fence. We returned to the north edge of the Black Rock Desert and turned NE again on Soldier Meadow road. We decided not to drive on the playa as it had showered much of the day and might have turned the track to mud. We passed an opal mine (formerly, Little Joe) and proceeded to the Mud Meadows Reservoir and turned south along the west flank of the Black Rock Range. This track follows the approximate route of the 49er’s as they treked to the Highrock Canyon and the Northwest. We passed the site of Hardin City, history unknown. Ruins consist of two eroded piles of cut ash fall tuff blocks that were buildings near a boggy spring.

Top, Hardin City Ruins – Bottom, Double Hot Springs

Some 5 miles to the south is Double Hot Springs, a series of pools with temperatures in the dangerous range. It was to late for a bath, so we turned back north a mile or so to a flat dry camping spot. It was windy and rainy all night but the area was surprisingly dry in the morning.

After breakfast and packing up camp, we re-traced our route to the north and found a track into the hills to the east. The area is reported to have a variety of chalcedony geodes weathering from basalt. We did find a number of specimens, nothing spectacular, and a lot of chips from sites along the flanks of the valley. Some were of a very pretty red jasper and had clearly been shaped as scrapers. The highlight, actually, was at the end of a small box canyon in one of the basalt layers where we found a nesting pair of prairie falcons. They were very upset with our visit but calmed down quickly as we left.

Seeing rain to the south and fearing a muddy track on the playa, we again headed south to Double Hot Springs. We took pictures and reflected on the marker with a quote from a log dated August, 1849, in which the writer remarked on the springs and the fact that they had rested and “boiled beans” (in the springs) as they passed, on the way up the trail. We then headed SW to the track across the Black Rock where for 35-40 miles one can drive in nearly a straight line at 50-60 miles per hour. The dust plume was spectacular!