Tuesday, May 17, 2011

Gold Mines and Prospects

YAHOO! Its finished! The book on Gold Deposits in Wyoming is available at Amazon (ISBN-10: 1463692625 ).

For over 30 years, I've been very successful in finding gold and other mineral deposits. Anyway, I examined many properties over the years and found potentially $billions in precious metals and gemstones. In our new book, we list several that should be investigated for commercial amounts of gold. Here are a few examples of gold prospects that are just sitting out there waiting for someone to put some work into the ground.

Tennant property Located four miles from Encampment Wyoming in sections 21 & 22, T14N, R84W. This was described as a 6-foot-wide fissure vein in section 22 contains copper and some gold. Six tons of ore mined from the vein netted $400 in copper (at $0.20/pound). In section 21, three strike veins with gold, silver and lead assayed $15 to $112/ton (1927 prices). Some country rock schist is mineralized and was reported to assay 0.12 to 0.18 opt Au: the presence of gold in the vein and wall-rock needs to be verified and if can be verified, the property may provide an attractive prospect along with drainages downstream.

Purgatory Gulch mines Wyoming (Section 1, T13N, R84W & section 36, T14N, R84W). Includes the Golden Eagle claim. A group of short adits were driven into limonite-stained shears in gneiss. On the west side of the gulch, two mines were examined by me in 1984. The southernmost was driven into granodiorite gneiss along a narrow shear. Four narrow copper- and limonite-stained veins were intersected in the mine workings. A short distance north, a short adit was driven <100-feet into the country rock. Across the gulch, more workings were found, but the adit was caved.

Some remarkably rich gold specimens were found in the past (Beeler, 1905a). According to Armstrong (1970), a 10-foot wide free-milling gold vein was struck on Purgatory Gulch. Assays ran as high as 6 opt Au (ounces per ton gold). More recent samples collected from the Golden Eagle vein contained visible gold (samples with visible gold typically assay >1 opt Au) and one boxworks-quartz sample without visible gold assayed 1.3 opt Au and 0.12 opt Ag (ounce per ton silver) (Hausel, 1989, 1992b). Another sample assayed 0.013% Cu (copper), 0.13 opt Ag, and 0.6 opt Au (Hausel, 1988d).

Even though these veins are narrow at the surface, it is possible that the vein could swell or pinch at depth which is common in metamorphic terrains. For example, one mine visited by the senior author near Yellowknife in the Northwest Territories of Canada was developed on an auriferous vein that was only 1 foot wide on the surface but swelled to over 6-feet wide at shallow depth.

Because of the high gold assays and presence of visible gold, eluvium surrounding the mines and prospects as well as gravels in Purgatory Gulch should provide some interesting metal detecting. This area is highly recommended for prospecting and specimen collectors.

Three Forks group Sections 11, 12, 13 and 14, T12N, R86W, located about 14 miles from Battle. Smoky quartz veins in schist are reported to contain argentiferous galena with minor sphalerite and copper. The veins have abundant hematite near the surface and both the quartz and hematite are reported to be auriferous (Pease, 1905). Some cerargyrite (silver chloride) is present (Osterwald and others, 1966). At least 500 feet of development work was completed on the property in the early 1900s.

The Three Forks vein is reported as well-defined and mineralized over a strike length of 6,500 feet and extends from the south bank of the North Fork River continuing from Wyoming and south into Colorado. The vein trends N25°W and dips 82°NE and is hosted by diorite. At one point, the vein (or complex of veins) is 120 feet wide. A 54-inch streak on the footwall side of the vein carried approximately 10% Pb (lead) and averaged $30 in lead, silver and gold (1905 prices) (Pease, 1905). Down-slope from the Three Forks group (sections 13 and 14) are the Pease placers. The gravels of the placers contain gold (Beeler, 1905f).

Probably the best nickel prospect in Wyoming was discovered by myself several years ago. The prospect was unrecognized as was the pyroxenite massif that it was found in which is known as Puzzler Hill located near Saratoga, Wyoming.

SW section 25, T14N, R85W. A mine with a main shaft situated on the contact of a sheared metadolomite and quartz chlorite schist was dug to explore a hematite gossan. Small amounts of malachite occur on the dump. A sample of chlorite schist yielded 1.5% Cu (copper) and 0.1% Ni (nickel) and a sample of gossan yielded 300 ppm Cu and 200 ppm Ni (Schmidt, 1983).

During the 1980s, the entire 450 mi2 South Pass greenstone belt was mapped along with all accessible historical mines (Hausel, 1991a). The geology was mapped at a scale of 1:24,000 on eight quadrangles and compiled into a 1:48,000 scale map for the entire exposed greenstone belt. All accessible underground gold mines were mapped at scales of 1:120 or 1:240 to provide a unique perspective of the structures that controlled gold deposition. It became apparent that the region is far from being mined out and that the gold mineralization was barely touched. The belt likely hosts considerable gold and iron ore along with a few major gold deposits. There is evidence for large gold deposits in shear zones, placers and paleoplacers. Iron ore resources, although mined for nearly 20 years, includes significant unmined resources quantities.

Placer deposits at South Pass have coarse gold near these shear structures. Further downstream, the gold is finer in grain size. Dredging operations on Big Atlantic Gulch in 1911 recovered nuggets weighing 0.07 ounce to more than an ounce. The ET Fisher Company dredged Rock Creek from 1933 to 1941 and recovered 30,000 ounces of gold: 75% of the gold was found within 3 feet of bedrock. Many nuggets were recovered near Atlantic City and the largest known nugget weighed 34 ounces: gold-bearing boulders were reportedly recovered that had as much as 630 ounces. Dredges operated along Rock Creek, Big Atlantic Gulch and at Wilson Bar in the Sweetwater River. Dredges are known to lose some gold to tailings as has been shown by many nuggets being found by nugget hunters using metal detectors to search tailings over past decades. In one case, we met one nugget hunter who had recovered more than 100 nuggets from dredge tailings near Atlantic City.

Large sections of many drainages at South Pass were not dredged indicating a potential for considerable gold-bearing gravel downstream from the gold-bearing shear zones. Placers of interest should include Rock Creek and Big Atlantic Gulch which have been extensively mined in the past, but still have unmined gravel and even gold-bearing tailings. Other drainages include Willow Creek, Strawberry Creek, Little Beaver Creek, Beaver Creek, Twin Creek, Meadow Gulch, Yankee Gulch, Spring Gulch, Horace Gulch, Smith Gulch, Promise Gulch, Irish Gulch, Omara Gulch, Jones Gulch, Level Meadows, Deep Creek, Sweetwater River, Burr Gulch, Wilson Gulch, Lame Jack Gulch, Long Gulch, Deep Gulch, Carissa Gulch, Palmetto Gulch, Slaughterhouse Gulch, Pine Creek, Big Hermit Gulch, Little Hermit Gulch, Buckeye Gulch, Cutler Gulch, Arasta Gulch, Slate Creek, Sheldon Gulch, Anthony Gulch, Beer Garden Gulch, Basket Gulch, Little Atlantic Gulch, Cole Gulch, Placerita Gulch, Tabor Gulch and possibly Dead Ox Gulch. Willow Creek, Strawberry Creek, Carissa Gulch, Smith Gulch, Rock Creek and Big Atlantic Gulch will likely contain considerable gold, and the report of several nuggets recovered from Big Nugget Gulch (Two Johns Gulch) suggests that area will be of interest.

Digging for gold in the dry Dickie Springs paleoplacer at the southern margin of South Pass. (a) Some cobbles and boulders at the top of the pit are rounded indicating stream transport and reworking of the paleoplacer. These reworked deposits are likely to be enriched in gold particularly where there is enrichment of black sands. But many cobbles in the pit walls are angular as seen near the geologist’s foot indicating that this portion of the paleoplacer is part of a fanglomerate that did not transport far from its source. (b) Gold was found throughout this entire section, but the gravel exhibited low gold content where cobbles are angular suggesting there was little stream transportation and concentration of gold and black sands in the fanglomerate at the bottom of the pit compared to the conglomerate at the surface. Some gold panned from the dry placer (below). Note the angular flakes.

Gold paleoplacers (ancient dry placers) cover large areas of South Pass. These are found within the greenstone belt and along its margins. Scattered paleoplacers sit immediately south of Atlantic City in the South Pass Formation and are recognized by the presence of rounded boulders in flat areas away from the modern drainages. Most of these have been overlooked even though they contain gold.

At Oregon Buttes to the south, Wasatch Formation conglomerates are estimated to be 1300 feet thick in areas and cover 8 mi2 of surface area. This Tertiary paleoplacer hosts a major gold resource with as much as 28.5 million ounces according to estimates by the U.S. Geological Survey. Some gold-bearing oil well cuttings were recovered in this region from depths of 6500-7000 feet just 0.5 mile north of the Continental Fault adjacent (north) to the paleoplacers (Dave Love, personal communication): this would indicate the presence of a buried auriferous shear zone at depth.
Generalized map of the Lewiston gold
district, South Pass (From Hausel, 1989

Wolf (Ruby) Mine (SE section 22, T29N, R98W). The Wolf mine is located to the northwest of the Atlantic City road. Three shafts (<100 feet deep) were sunk on a 4,500 foot long hematite-stained chloritized shear zone. The shear is not well-exposed but is as much as 160-feet-wide. The structure lies within a subtle linear depression. The width of the structure was determined by trenching and the depression continues to the northeast and southwest from the shafts.

The footwall on the 78oNW-dipping shear is silicified. One grab sample of gray quartz with altered metagreywacke assayed 0.68 opt Au. Samples collected across this shear assayed >1.0 opt (Steve Gyorvary, personal communication, 2010). The property was examined by U.S. Borax who determined the structure to be mineralized over >100 feet of width. This structure, because of potential size and assays, should be thoroughly investigated and likely represents a significant gold deposit.

Duncan mine (W/2 W/2 section 14, T29N, R100W). Gold production from the Duncan mine was at least 3,800 ounces (Hausel, 1980). The property is located about one-mile southwest of Atlantic City. The main strike shear (N80oE) is hosted by Miners Delight Formation amphibolite (metagabbro) intruded by a metatonalite plug at the western edge of the property. The foliation-parallel shear is folded and splayed producing a classical saddle reef ore shoot adjacent to the shaft. The splay has an aggregate width of >40 feet adjacent to the shaft. Within the fold closure, gold values are enhanced and the nose of the steeply plunging drag fold averages ten times more gold than in the fold limbs. Samples collected in the glory hole next to the shaft included a 2-foot channel sample of 1.06 opt Au. A 39-foot composite chip sample assayed 0.073 opt Au.

Duncan Mine sample description           Au(opt)         Ag(opt)

0 to 2 ft west of fold closure in shear       0.097              0.07
2 ft channel across fold closure                1.06                0.19
0 to 5 ft east of closure                              0.06               0.06
5 to 15 ft east of closure                            0.21               0.09
15 to 25 ft east of closure                          0.023             0.24
25 to 35 ft east of closure                          0.02               0.032

The Duncan mine as it appeared to the author in 1977.
The extent of the mine workings is unknown, although Jamison (1911b) reported at least 1,255 feet of drifts on the 250 foot level. The mine workings need to be mapped. Based on the surface samples, it is likely that a significant gold deposit occurs on the property. The ore tenor was reported as 0.25 to 5.25 opt Au. Like all mines in this district, only the high grade ore was pursued and all low grade ore (which would be considered economic today) was ignored.

Anaconda Minerals drilled four locations on the property in 1974. The data showed the mine to enclose an incompletely explored, 925-foot long mineralized shear that was a minimum of 0.7 to 7 feet wide.

Drill Hole Description Width of zone Au (opt)

DDH9 Intersected two mineralized zones Zone 1 – 7 feet wide 0.18
Zone 2 – 2.1 feet wide 0.11

DDH10A Drilled 375 ft west of DDH9 Zone 1 trace
Zone 2 - 0.7 ft wide 0.17

DDH11 Collared 550 ft west of DDH10A Zone 1 trace
Zone 2 - 5.7 ft wide 0.025

MIRACLE MILE PLACER. Little is known about the Miracle Mile paleoplacers such as extent, thickness, gold content, diamond content. This deposit was discovered by Charlie and Donna Kortes and could represent a good place for prospectors to search for gold and diamonds as it is a relatively new discovery. Because much of the deposit sits high and dry in the flats between Kortes Dam and Pathfinder Reservoir and on both sides of the North Platte River, metal detectors might be used to find nuggets but much of the finer gold would have to be recovered with dry placer recovery systems. The area remains mostly uninvestigated because recent directors of the Wyoming Geological Survey have had an anti-mining agenda and would not fund this kind of basic exploration research

Raw diamond with surface trigons
Samples of gravel with visible gold were panned from conglomerate. After being shown this area by Charlie and Donna Kortes, we discovered that the placer also contains numerous pyrope garnets. Nearly all of the garnets that were microprobed at the University of Wyoming yielded harzburgite geochemistry. In other words, most appear to have eroded from a nearby diamond-rich kimberlite pipe (Hausel, 1994c)! It is apparent that this paleoplacer also has potential for placer diamonds (along with gold) and somewhere nearby is an undiscovered diamondiferous kimberlite field! It seems that nearly everywhere we sampled in Wyoming for gold or diamonds, we found diamond indicator minerals! In Canada, exploration research typically costs about $1.5 million per discovery! In Wyoming, the State government often spent less than $1,000/year on basic exploration research, yet hundreds of anomalies were identified. Makes one wonder what would happen if the Wyoming Geological Survey actually had a director with vision?

The samples were only taken from a few sites within a mile of the North Platte River near a powerline: the rest of the paleoplacer is untested, although the gold is reported to be widespread (Charlie and Donna Kortes, personal communication). You can find this area by searching GOOGLE EARTH for Kortes Dam, Wyoming.


  1. Wow, what an amazing wealth of knowledge. Thank you so much for putting this together. Being recently disabled with a severe form of neuropathy I have been looking for a hobby to keep me busy when I feel up to moving around. We will be moving to Pinedale from Iowa and I may just have to spend some more time researching and get into a little prospecting to get enough money to make ends meet. Anyways, thank you again for the information!

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