Monday, November 18, 2013

HAHNS PEAK, COLORADO



If you don’t know where you are going, you might wind up someplace else (Yogi Berra).

I have always enjoyed looking at geologic structures and hunting for minerals and fossils at “off the beaten path” localities; hence, my yearning to once again travel to Hahns Peak, Routt County, Colorado.  I first visited the area in the late 1960’s and again in the late 1970’s.  However, this time I was determined to better understand the area’s geology, and to summit the peak.  So, begin my recent trip.
 

Hahns Peak looking east from the parking lot; ready for the trek to the summit.
Hahns Peak is not that difficult to locate—just drive about 30 miles north of Steamboat Springs on Routt County RD 129.  However, Hahns Peak is essentially the final destination as the paved road changes to gravel and FR 129 wanders north and west and really never goes anywhere except perhaps to Baggs,Wyoming about 50 miles away, part of it via 4-wheel drive!  Most travelers on RD 129 today are heading to Steamboat Lake State Park or Pearl Lake State Park, both a few miles south of Hahns Peak.  Unfortunately, the area is vastly different today than 30 years ago as the “pine beetle disease” has ravished the landscape.

Hahns Peak is somewhat of a geographic enigma and physiographers are unable to assign it to a specific mountain range.  It seems geologically connected to the Elkhead Mountains to the west rather than the geologically complex Sierra Madre Range (part of the larger Park Range) to the east.  The Elkheads are tied to Hahns Peak since both areas have abundant Miocene igneous rocks.   Most of the rocks in the Elkhead Mountains are Upper Cretaceous to Tertiary sedimentary rocks crisscrossed by 7.6 to 11.5 Ma igneous rocks occurring as hypabyssal stocks (magma originates within the earth’s crust and starts toward the surface but ends up cooling before reaching the surface), sills (igneous rocks intruded parallel to the bedding), and dikes (igneous rocks intruded at an angle to the bedding).   Intrusive rocks in the Elkhead Mountains are mostly alkaline (usually high in potassium and sodium) forms of such rocks as basalt and rhyodacite and their coarse-grain equivalents.  Around Hahns Peak the igneous rocks are more felsic in nature, that is, the rocks are enriched in silicate minerals (Bankey and others, 2000).  At Hahns Peak itself the stock is composed of quartz latite, now partially hydrothermally altered to a porphyritic rhyolite (Dowset, 1980; Segerstrom and others, 1972).  What this means is that the main unit at the center of Hahns Peak has a fine groundmass with large feldspar phenocrysts.  In addition, I was able to locate numerous dikes and a few hornfels (the sedimentary shale has been heated, and changed, by the contact with the hot magma).  All of these igneous rocks were intruded into earlier formed Precambrian rocks and an overlying sedimentary section of Triassic, Jurassic, Cretaceous, and Tertiary rocks.  One of the units of the Mancos Shale (Cretaceous) has hard siliceous shale where I was able to collect numerous fish scales.  These last few sentences are quite complex; however, geologists can interpret much about the history of igneous rocks by examining their mineral composition.  I need to leave it with saying that Hahns Peak seems most closely related to the Elkhead Mountains, and that intrusive igneous rocks form the core of the Peak. 
 

Approaching the summit of Hahns Peak.  Note the cream colored intrusive rock that forms the center of the peak.  The structure on the summit is a U. S. Forest Service fire tower (no longer in use).
Hahns Peak was the site of a somewhat major “gold rush” beginning in the 1860’s.  Parker (1974) gleaned the following information from an 1895 book on the history of Colorado written by Frank Hall: “the Hahns Peak placers were discovered by Captain Way in 1864.  He returned to Empire and told John Hahn of his discovery.  The following year Hahn, with W. A. Doyle, went to the area and prospected it.  They returned in 1866 with a party of 40 men who built cabins near the site of Hahns Peak Village and placered through the summer.  These men established a mining district, naming it and the peak in honor of Hahn.  Faced by an early winter that year, the men returned, leaving Hahn and Doyle.  During the spring of 1867 these two men were forced to return to Empire for supplies and were caught in a severe snowstorm on the Gore Range, where Hahn died.”  I have noted other references stating Hahn’s name was Joseph and that he “discovered” the gold in 1862.  At any rate, Hahn left behind his legacy in the name of a mountain, Hahns Peak at 10,839 feet.  Certainly not the highest peak in Colorado, but: 1)  the SNOTEL (weather station for measuring snow depth) site on Hahns Peak consistently measures some of the greatest snowfalls/depths in the state of Colorado; and 2) timberline on Hahns Peak is perhaps the lowest on any peak in Colorado at 10,300 feet (www.summitpost.org). Hahns Peak is capped with a fire-lookout that was built in 1912 and reconstructed in 1942. The fire lookout lasted only until the 1950's because of frequent lightning strikes.  And finally, it seems the peak is always spelled as Hahns Peak rather than Hahn’s Peak!

Another enigma associated with the Peak is that virtually all gold extracted from the district is placer gold and the exact source for the precious metal has never been fully located.  Perhaps the source rocks were eroded away and now form the secondary (placer) source?

Several mines were constructed on the Peak attempting to locate significant reserves in the central porphyry pipe, the most prominent mines being the Minnie D. and the Tom Thumb.  However, “no important ore deposits have been found in the Hahns Peak District” (Parker, 1974).  There do seem some anomalous reports, however, as George and Crawford (1909) noted that “a 9-ton shipment ran 2 oz gold and 52 oz silver per ton with 51.8 percent lead”.  In today’s world two ounces of gold per ton of ore would seem rich; however, none of the gold was/is free gold so these rocks seem not the source of the placer gold.  But, before one jumps into the prospecting and mining game, consider the more recent reports.  Dowsett (1980) noted that mineralization in the quartz latite stock at Hahns Peak was in the form of “lead-zinc-silver sulfide”.   Bankey and others (2000) stated that “samples from the Hahns Peak mining district... contained anomalous concentrations of antimony, arsenic, lead, molybdenum, silver, and zinc… probably related to disseminated silver-lead-zinc mineral deposits associated with the Tertiary Hahns Peak porphyry stock.”  There was no mention of gold. 
 

Closed mine shaft below summit of Hahns Peak.
So, the great majority of gold in the district is placer gold with the major deposits being: 1) Poverty Bar, just west of Hahns Peak Village and now mostly covered by Steamboat Lake; 2) and Ways Gulch southeast of Poverty Bar and east of Hahns Peak Village.  Both of these deposits probably represent alluvial fans radiating off the Peak.

How much gold was taken from the Hahns Peak District—a question for the ages!  Voynick (1994) reported that the placers produced 10,000 troy ounces and hard rock mines $200,000 of lead, copper, silver and gold (prices calculated when?).  George and Crawford (1909) noted that estimates ranged from $200,000 to $15,000,000 with the more conservative estimates being $200,000 to $500,000.  But, the price of gold in 1909, at the time of their publication, was $18.96 ounce.  In today’s market the price was $1373 per ounce.  Could a conservative estimate of $200,000 turn into 14.5 million dollars today?  I suppose that we will never know.

The boom years for gold mining in the Hahns Peak District were during the 1860’s and 1870’s.  By around 1880 the major boom was over but sporadic mining remained.  Burchard (1882; 1884) estimated production in 1881 as $20,000, in 1882 as $15,000, and in 1884 as $40,000.  Dredges were brought in during the late 19th and early 20th centuries but I could not locate production figures; however, they were probably small.  Since the 1920’s there have been small-scale attempts to resurrect the mining but evidently they were unsuccessful.  Even today observers may note evidence of prospecting.
 

Summit porphyritic rhyolite with voids left by tabular feldspar phenocrysts.
The climb to the summit of Hahns Peak is exhilarating and a great hike “before breakfast”!  Two weeks into June I was breaking through snow crust on the trail and was one of the earliest summer hikers.  The Cretaceous Dakota Formation is well-exposed on the lower part of the trail and has a widespread conglomerate unit.  The central core of the mountain, the altered quartz latite, has large phenocrysts of feldspar, many of which have weathered out leaving a void.  Pearl (1972) noted the occurrence of large clear quartz crystals near the summit.  However, I was unable to locate good specimens.  Perhaps I needed some strenuous “digging” to locate the cavities containing the five inch crystals.  The view from the summit is quite spectacular with the high Sierra Madre Range directly to the east and the Elkheads to the west.  To the far south the volcanics of the Flattop Wilderness are evident.  And with binoculars I could spot my campsite at Steamboat Lake.

Looking southwest from the summit of Hahns Peak.  Note Steamboat Lake with peaks of the Elkhead Mountains. 
 

Hahns Peak, elevation 10,839 feet.
If you visit the area make certain to stop in at the Columbine General Store dating back to the mid 1880’s.  This “ghost town” lies near the base of the mountain and near where the pavement ends and was an important location during the mining days.  A few miles to the south several historic buildings from the mining days, including the “Little Green Schoolhouse” museum, are well preserved in the Hahns Peak Village, the first county seat of Routt County.

In 1901 the Laramie, Hahns Peak, and Pacific Railway Company was established to support the gold fields in the Medicine Bow Mountains west of Laramie but was late to the party as much of the mining had fizzled out.  So, it became a coal railroad and purchased mines south of Walden, Colorado in North Park reaching the area in 1911.  North Park is east of the Sierra Madres so I often wondered why they incorporated the name “Hahns Peak” into their name?  Perhaps they had visions of reaching the mines.  At any rate, the railroad was sort of a scam and several investors lost money.  Amazingly, the railroad struggled on, under a variety of names, until 1987.
 

Gravity water tank and coal train of the Laramie, Hahns Peak, and Pacific Railway Company at Spring Creek, Albany County, Wyoming.   Photo courtesy of Wyoming Tales and Trails.
Before my hike I sat on a rock and read a small poem written by Rose Wheeler (an early settler) with one stanza being:
I look up at the mountain,
And my soul with rapture fills,
For as I gaze, it seems
That God is smiling down on me

REFERENCES CITED

Bankey, Viki, S. J. Soulliere, and M. I. Toth (eds.), 2000, Mineral Resource Potential and Geology of the Routt National Forest and the Middle Park Ranger District of the Arapaho National Forest, Colorado: U. S. Geological Survey Professional Paper 1610.

Burchard, H. C., 1882, Report of the Director of the Mint upon the Statistics of the Production of the Precious Metals in the United States (1881):  U. S. Treasury Department, Bureau of the Mint.

___________., 1884, Report of the Director of the Mint upon the Statistics of the Production of the Precious Metals in the United States (1883):  U. S. Treasury Department, Bureau of the Mint.

Dowsett, F. R., 1980, Hydrothermal Alteration of the Hahns Peak Stock, Routt County, Colorado: Economic Geology, v. 75, no. 1.

George, R. D. and R. D. Crawford, 1909, The Hahns Peak Region, Routt County, Colorado, an Outline Survey: Colorado Geological Survey 1st Report.

Parker, B. H., 1974, Gold Placers of Colorado, Book 2: Quarterly of the Colorado School of Mines, v. 69, no. 4.

Pearl, R. M., 1972, Colorado Gem Trails and Mineral Guide: Swallow Press, Athens, OH.

Segerstrom, K. and E. J. Young, 1972, General Geology of the Hahns Peak and Farwell Mountain Quadrangles, Routt County, Colorado with a discussion of Upper Triassic and Pre-Morrison Jurassic Rocks by G. N. Pipiringos: U. S. Geological Survey Bulletin 1349.

Voynick, S. M., 1974, Colorado Rockhounding: Mountain Press Publishing Company, Missoula.