The Yogo district is located in a relatively remote area east of Neihart and south of Stanford on the east slope of the Little Belt Mountains along Yogo Creek. Placer gold attracted the initial rush of miners, while deposits of silver, lead, and iron ore supported small scale lode mining for a number of years. It was the discovery of sapphires, however, that brought fame to the Yogo district.

Sedimentary rocks underlie the area and include limestones, shales, and sandstones from the Precambrian to Carboniferous periods. Igneous rocks have intruded into the host rocks, and mineral deposits are found at or near the contact zone. The primary minerals are galena, pyrite, and chalcopyrite, along with their oxidation products. Iron ore is found in lenses and bands within the Madison limestone near the zone of contact. Sapphires are found "in a minette or lamprophyre dike that cuts flat-lying Madison limestone" (Weed 1900; Robertson and Roby 1951; DeMunck 1956).

Following the initial discoveries of placer gold in Montana, miners fanned out to locate new deposits. Some evidently found gold on Yogo Creek about 1865, but did not stay long when Native Americans became hostile. Other prospectors later returned to the area, and their discovery of gold along Yogo Creek in 1879 brought a rush to the remote region. The short-lived town of Yogo mushroomed to a population of 1,200-1,500 at its peak (Weed 1900; Robertson and Roby 1951).

Miners constructed a number of miles of ditches to bring water to work their claims, which extended along the main creek for six miles on either side of the camp. Remnants of these ditches remain, including a section near Morris Creek (Weed 1900; Keim 1991).

While most worked claims along Yogo Creek, others worked ground in tributary creeks such as Skunk Gulch. At the end of the first season, however, the return was so small that the population rapidly dwindled. Just four years after its discovery, Yogo Gulch was all but deserted. A few miners continued placering in the alluvial gravels, and two men reported making fair wages in 1897 working a small hillside claim. A small population remained in the area for many years (Weed 1900; Lyden 1948; Robertson and Roby 1951; Hay 1975).

While the placering did not pay off, a number of prospectors staked lode claims in the Yogo district. Discoveries concentrated in the area north and west of Yogo camp, especially in Skunk and Elk gulches. The Blue Dick mine was located in 1878, the Gold Bug (Weatherwax) the next year, and most others in the following decade. Aside from the Gold Bug, there was little development work on the mines until the late 1880's and 1890's. The Blue Dick, California, Della and Quaker City, Gold Bug, Little Emma, and T. C. Power were all worked during this period. None contained much high-grade ore, however, and apparently most activity ceased by the turn of the century. The Blue Dick, California, and Gold Bug all experienced revivals during the 1930's and 1940's, and the New Deal was probably worked during the same time (Weed 1900; Robertson and Roby 1951).

Due to the remote location of the Yogo mines, there were a number of small mills set up in the district to process the ore. Elias Shelby operated a water-powered arrastra at Yogo, grinding ore in two "tubs." He processed ore from the T. C. Power mine in 1889 and may have been responsible for milling ore from the Blue Dick four years later. Accounts differ for the arrastra associated with J. D. Weatherwax's Gold Bug mine. Robertson and Roby (1951) claim that he built an arrastra on Skunk Creek, while Hay (1975) recalls that Weatherwax packed the ore to Yogo where it was crushed in the same arrastra that processed ore from the T. C. Power mine. Weatherwax later replaced the plant with a five-stamp mill (Swallow and Trevarthen 1889; Weed 1900; Robertson and Roby 1951; Hay 1975).

Operators in the 1930's and 1940's also established local milling facilities. While the owners of the New Deal mine erected just a small gravity mill, the Blue Dick Mining Co. built a 50-ton gravity flotation mill in Elk Gulch to work ore from the mine. Lessees at the Gold Bug took a different approach, shipping ore to the smelter at Anaconda. In addition, both sapphire mines had milling facilities that are described in detail below (Robertson and Roby 1951).

Continued placering for gold led to the unexpected discovery of sapphires in Yogo Gulch. Different versions of the story provide details and often conflicting information. A group of men worked the gravels of a bench east of Yogo Creek during the summer of 1895, constructing a $38,000 ditch to bring water to the claims; remnants of this ditch and flume can be traced for several miles from west of Bear Gulch east-southeast to the sapphire mines (Hamlett 1984). Weed (1900) does not provide names of the miners; Robertson and Roby (1951) lists the men as G. A. Wells, S. S. Hobson, Matthew Dunn, and J. Hoover; and Wolle (1963) names a partnership of Jake Hoover, Frank Hobson, S. S. Hobson, and Dr. J. A. Bouvet. The investment failed to pay, however, since the season's cleanup amounted to only $700.

The sluices lacked gold, but the men noticed that they contained a number of blue pebbles. Weed (1900) reported that these were identified as sapphires and New York's Tiffany & Co. paid $3750 for a cigar box full of the gems. Robertson and Roby (1951) claim that Tiffanys paid only $1,800 for the rough sapphires. Wolle offers still two other versions. In one story, Frank Hobson sent a sample of gold to a teacher friend in Maine, including some of the blue pebbles for interest; she wrote back to thank him for the sapphires. In the other account, Jake Hoover asked other miners about the strange stones; S. S. Hobson's initial identification as sapphires was then confirmed by a Helena jeweler. Unlike other Montana sapphires, those from the Yogo deposits are valued for their cornflower blue color and exceptional brilliancy (Robertson and Roby 1951).

While Hoover and others set out to wash the creek gravels for sapphires, a local settler named John Ettien accidently stumbled on the sapphire lode when he was prospecting near the placer operations. He found a fissure in a limestone outcrop with a soft filling that looked like a vein. Ettien staked two claims, washed some dirt, and immediately found blue sapphires. Hoover and others quickly recognized the dike as the source of the Yogo sapphires. Miners traced the vein for at least five miles and staked claims along its length (Weed 1900).

New Mine Sapphire Syndicate, a British company, purchased claims along the eastern end of the dike in 1897, while American Sapphire Co. (succeeded by Yogo Lapidary Co. and Yogo American Sapphire Co.) bought claims about the same time at the western end. The two companies mined the vein until 1914 when the British syndicate bought out its competitor, controlling all 33 patented claims. It continued operations until 1929 (Robertson and Roby 1951).


The only written descriptions of the Yogo district outline the traditional boundaries, which include the headwaters of Yogo Creek in the Little Belt Mountains.

According to Robertson and Roby (1951):

The Yogo district includes the area south and east of the divide between Yogo and Running Wolf Creeks and the area around the headwaters of the Middle Fork of the Judith River as far south as the main divide along the southern border of the county.

DeMunck (1956) has slightly different boundaries for the district: "The Yogo district includes part of Ts. 13 and 14 N., and Rs. 9 and 10 E. The area forms the divide between the headwaters of Yogo Creek in the south and Running Wolf and Dry Wolf Creeks in the north."

Figure 1 shows a large Yogo district as defined by the AMRB (1994) with the headwater of Yogo Creek outlined as the historic mining area and the sapphire mining area shown as a sub-district.


Blue Dick

One of the first mines in the district, the Blue Dick was located in 1878 but not patented until 1892. The mine consists of three patented claims on the west slope of Elk Gulch in Secs. 30 and 31, T14N, R10E. Gold occurs in the mine as a contact replacement deposit. P. H. Hughes operated the mine in 1893, processing the ore for gold in an arrastra at Yogo. The results may have been discouraging since Weed (1900) found that a sample of oxidized ore contained only a trace of gold and 2.2 ounces of silver per ton. There are no production records from these early operations (Weed 1900; Robertson and Roby 1951; Woodward 1991).

The mine may have been idle during the early 1900's, but it was back in operation by at least 1937. The Blue Dick Mining Co. constructed a 50-ton gravity flotation mill in 1943, not far below the mine in Elk Gulch. After a surface tram connecting the mine and mill failed to work well, the company built a road for hauling ore. Mine workings include an open cut, a 325-foot upper adit, and a 400-foot lower adit. The Blue Dick produced 702 tons of ore from 1937-1946, yielding a total of 329 ounces of gold, 3231 ounces of silver, and 23,667 pounds of copper. DeMunck (1956) noted that ore from the Blue Dick also contained up to 60 percent iron (Robertson and Roby 1951).


This group of claims is located along the top and east side of Prospect Ridge, about one-half mile south of the lookout tower on Yogo Peak. The claims were first located in the early 1880's, but they have been abandoned and relocated more than once. Deposits at the western end of the group contain galena in altered limestone; operators have worked the area with trenches but have shipped no ore. Claims along the eastern side of the ridge are staked along a syenite porphyry dike, and a residual gold deposit with free gold, covering approximately one-half acre, occurs where the dike has weathered. Individuals have placered this deposit off and on, but work has been hindered by a lack of water. Operators at one time laid 4000 feet of pipe to bring water from a spring but used it for only four hours or so. This brief period was very productive, however, recovering 8 ounces of gold in a 50-foot sluice. Additional workings include a 100 foot adit, a 100 foot shaft, and small trenches from which operators mined a few tons of low grade gold ore. There are no records of production from the mine (Robertson and Roby 1951).

California (Harriet)

The California unpatented claim is found close to the top of the ridge on the east side of Elk Gulch, about one-half mile south of the divide between Elk and Lyon gulches. Although it was staked in the early 1880's, the claim was probably not worked much until the following decade. The Judith Valley Mining and Milling Co. owned the property in 1897 when Louis Pepin, R. Giroux, and Joseph Sutler sank a 50-foot shaft on the vein. Assays showed $7 per ton in gold from the ore, which is a contact replacement deposit. Despite considerable development work, including a 150-foot adit, 100-foot crosscut, and the shaft, the mine was abandoned. Harry F. Goll relocated the claim in 1942 or 1943, renaming it the Harriet. He reopened the adit and sampled the ore but did little other work. There are no production records for the mine (Weed 1900; Robertson and Roby 1951; Woodward 1991).

Della and Quaker City

Located at the head of Elk Gulch, on the divide between it and Lyon Gulch, these claims were worked intermittently for several years after 1892. Charles Ferris and M. R. Dornblut owned the property in 1893 when they drove a 300-foot adit drift to follow a minette dike. The ore in this area contained free gold in a 2-3 inch band. The mine was inactive by 1897. In addition to the long adit, the mine included a shaft and other adits. There are no production records from the mine (Weed 1900; Robertson and Roby 1951).


The Finlander group encompasses six patented claims on the north side of Yogo Peak in Sections 25, 26, 35, and 36, T14N, R9E. Discovered around 1900, the claims were patented in 1919. A 96-foot shaft and 600-foot adit were used to reach the copper and iron ore which ranged from 20-28 feet in width. The ore was found in a contact metasomatic deposit. There are no production records for the mine (Robertson and Roby 1951; DeMunck 1956; Woodward 1991).

Gold Bug (Weatherwax)

J. D. Weatherwax located the Gold Bug mine around 1879. Eleven claims cover 220 acres on the west side of Skunk Gulch about two miles north of Yogo. Weatherwax developed the mine and may have built an arrastra close to Skunk Creek to process the gold ore. The early returns encouraged Weatherwax to plunge into development work. He and his sons constructed four miles of road, two cabins, and a mill building with a five-stamp mill. Within a short time, however, the ore changed to a non-free milling type, and the mill was useless. The Weatherwax family continued to work the mine on a small scale, crushing and retorting the ore in small batches until they accumulated a reported $3000 in gold (Weed 1900; Robertson and Roby 1951; WPA 1940; Hay 1975).

Sometime after that, Weatherwax was killed in an accident near the mine and ownership of the Gold Bug transferred to Andrew Hay. He and his extended family continued to work the non-free milling ore and shipped two wagon loads to the smelter at Great Falls. Smelter returns were based on an assay of $70 in copper and $15 in gold per ton. Because of the high costs of freighting, the operators then decided to build a small smelter at the mine. They brought in firebricks, iron, and slag pots, but never got any farther with the project. The family continued to do annual assessment work until World War I and eventually abandoned the mine (Hay 1975).

Carl Nordberg and H. R. Trimmer of Lewistown relocated the mine about 1930 and began a period of extensive work. Walter Lehman leased the property in 1937, working it intermittently until 1946. By circa 1940, Lehman employed three men and had reported "approximately $30,000 total production to date." Smelter receipts for later production indicate that Lehman shipped 14 cars of sorted ore, amounting to 508.52 tons, to the Anaconda smelter and received $6002.81 in return. The ore contained 0.23 to 0.74 ounces of gold, 0.37 to 6.6 ounces of silver, and 0.77 to 3.96 percent copper per ton. Mine workings include open cuts, three adits, a shallow shaft, and close to 1,200 feet of underground tunnels (Robertson and Roby 1951; WPA 1940).


The Leonard mine consists of two silver-lead claims located near the Forest Service road one mile southwest of the lookout tower on Yogo Peak. At least one early miner claimed and abandoned the deposit before Joe Boucher of Havre and Paul Vdovic of Neihart relocated it in July 1949. The mine workings at around 1950 included at one or more adits as well as a gasoline powered hoist and cables. At that time, there had been little work done on the deposit and no shipments of ore. The dump contained about one ton of ore, however, and a Bureau of Mines assay showed a sample contained 0.005 ounces of gold, 83.6 ounces of silver, 22.9 percent lead, and 0.1 percent zinc per ton (Robertson and Roby 1951).

Leonard II

This group of magnetite claims is located in Sections 4 and 9, T13N, R9E. The dump contains a good grade of ore that assayed at 63 percent iron. There are no records of production (DeMunck 1956).

Little Emma

Located west of the Blue Dick, this mine operated during the 1890's. Crews sank two 28-foot shafts and drove a tunnel 300 feet. Gold ore assayed at $17 per ton, but there are no records of production. Like the neighboring Blue Dick mine, the ore in the Little Emma is a contact replacement deposit (Weed 1900; Robertson and Roby 1951; Woodward 1991).

New Deal

The New Deal mine includes several unpatented claims located northeast of the Blue Dick mine in Sec. 30, T14N, R10E. The ore is a contact replacement deposit that consists mostly of magnetite, pyrite, and chalcopyrite. The mine was actively worked for a period from six adits. Operators constructed a small gravity mill near the mine and shipped a small amount of concentrate, with values mostly in gold. After abandonment, the claims were relocated. There are no production records for the mine (Robertson and Roby 1951; Woodward 1991; DeMunck 1956).

New Mine Sapphire Syndicate

Following the discovery of sapphires in placer deposits and the associated lode described above, the New Mine Sapphire Syndicate of London bought many of the claims on the eastern end of the dike in 1897. The company initially used simple hand mining methods to recover the gems, with workers hauling dirt by wagons to a sluice for washing. The company sank a 60-foot shaft in the dike that first year, and mining methods resembled those used in any underground operation (Robertson and Roby 1951).

Ore from greater depth was harder than that removed from open pits, and the company altered its recovery methods. The ore was first spread out two feet thick in a disintegration yard where it was wetted periodically and left to weather. This yard was about 250 feet square and was floored with planks 2 inches thick. After weathering, crews ran the ore through sluices with iron grated riffles set a few feet apart to trap the sapphires. Unlike gold placering operations, however, rock that passed over the riffles initially was not discarded, but was instead set aside to weather again. All of the ore was weathered and run through sluices four times before being thrown on the tailing pile. The rough stones were processed in an electromagnetic separator to remove pyrites, and then hand sorted. The company shipped the sapphires to London where the best quality were cut for gems while others were refined for watch jewels, instrument bearings, and abrasives (Robertson and Roby 1951; Rowe 1909; Freeman 1915).

New Mine Sapphire Syndicate purchased the holdings of its competitor, Yogo American Sapphire Co., in August 1914 for $80,000. Instead of expanding its operations, the company shut down the American mine, working its original claims until all sapphire mining ended in 1929. By that time, that shaft had reached 250 feet. The 100-foot level had 3,000 feet of tunnels while the 250-foot level had another 1,750 feet of workings. When last operating, the mine employed 35 to 75 men (Robertson and Roby 1951; WPA 1940).

During its 32 years of operations, the New Mine Sapphire Syndicate mined and processed 200,000 tons of ore, recovering nearly 13 million carats. Gem quality stones accounted for about 75 percent of the total value. The English company recovered 130,000 carats of gem quality stones in 1900, with the largest ones weighing 11-12 carats before cutting. From 1924-1927, the mine produced 903,685 carats valued at $86,562. Of these, 150,365 carats, worth $73,039, were gem quality, while 753,320 carats, worth $13,523, were usable for industrial or abrasive purposes (Pratt 1901; Robertson and Roby 1951).


The Sarsfield mine combines the Sarsfield, Ben Franklin, and Sheridan claims. They are located on a ridge between Bear Gulch and the upper north branch of Yogo Creek, in Sec. 36, T14N, R9E, and Sec. 31, T14N, R10E. The initial claimants, who located the mine in the 1880s, did a small amount of development work, primarily trenches and surface cuts, before abandoning the claims. A. J. Stough and H. R. Trimmer relocated the deposit c. 1914 and began a larger development project. The shaft reached 70 feet, with a crosscut and drifting to develop the deposit on the 60-foot level. In addition, the men drove a 450-foot adit 200 feet below the shaft collar. Despite considerable work, the claims were once again abandoned, only to be relocated in 1940 by H. R. Trimmer and C. R. Goyins. After driving another short adit, the partners shipped some copper ore from the Sarsfield claim. There are no production records for the mine (Robertson and Roby 1951; DeMunck 1956).

The principal minerals are magnetite, pyrite, chalcopyrite, malachite, cuprite, and chrysocolla. A sample of ore tested by the Bureau of Mines showed 0.035 ounces of gold, 0.25 ounces of silver, 0.99 percent copper, and 0.01 percent tungsten trioxide per ton (Robertson and Roby 1951; DeMunck 1956).

T. C. Power

One of the district's early gold mines, the T. C. Power is located on the ridge between Elk and Skunk gulches, about one- half mile south of the Gold Bug (Weatherwax) mine. Operators removed several tons of ore in 1889, milling it in Elias Shelby's arrastra at Yogo. The arrastra consisted of two "tubs" operated by an overshot water wheel. The ore yielded $10-$40 per ton in free gold. The mine was still in operation in 1893 but had closed four years later. There are no production records (Weed 1900; Robertson and Roby 1951; Swallow and Trevarthen 1889).

Yogo American Sapphire Co.

During the initial discovery of sapphires in the Yogo district, John Burke and Pat Sweeney located the Fourth of July placer claim on, appropriately enough, July 4, 1896. The mine went through a series of owners over the next 18 years. Burke and Sweeney sold to American Sapphire Co. Yogo Lapidary Co. then ran the operations from 1904-1909, selling to Yogo American Sapphire Co. Finally, New Mine Sapphire Syndicate purchased the mine in 1914 and immediately closed it down for good (Robertson and Roby 1951; Dahy 1991).

Mining methods on the seven claims were similar to those used on the neighboring New Mine Sapphire Syndicate properties. The ore was initially reached through two adits with crosscut drifting. Crews later sank a 300-foot shaft and developed three levels. Processing of the ore was quite different, however. The American mine ran ore through a concentrator set near the portal of the mine. The ore passed first through a 4-inch grizzly to a jaw crusher. The smaller pieces were then run through a series of sizing screens, followed by Woodbury jigs; the concentrates at this point averaged 5-10 percent sapphires. After treatment in a Blake-Morscher electrostatic machine, the final concentrates were 50-90 percent sapphires. Final cleaning and sorting was done by hand. Large pieces of ore were set out to weather before running through the concentrator again. The plant could process 75 to 100 tons of ore each day (Rowe 1909; Robertson and Roby 1951).

The concentrator recovered a much higher percentage of stones than the sluicing method used by the English company. Yogo American Sapphire Co. recovered nearly 95 percent of the small stones and close to 100 percent of the large gems. All of the mine's output was sold in the United States. Starting in 1903, many of the stones were cut and polished in a special department at the plant; three years later, some of the stones were sent to a new sapphire cutting plant at Great Falls. The mine had produced $30,000 worth of sapphires up to 1904. Operations picked up considerably after this, and the output for 1906 was $250,000. The total production of the Yogo American Sapphire Co. was nearly 3 million carats (Rowe 1909; Robertson and Roby 1951).


Abandoned Mine Reclamation Bureau (AMRB)

1994 Mining districts of Montana. Maps 1:100,000 and Map #94-NRIS-129. Compiled and edited by Joel Chavez. Prepared by Montana State Library Natural Resource Information System (NRIS) for Montana Department of State Lands. Helena

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1931 "Rubies and Sapphires", U. S. Bureau of Mines, Inf. Circ. 6471.


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Byrne, John and Frank Hunter

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DeMunck, Victor C.

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Ede, J. A.

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Ferguson, Henry Gardiner and L. P. Benedict

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Freeman, Otis W.

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1917 "Mineral Prospects in Fergus County", Eng. and Min. Journal, Vol. 103, pp. 660-662.

Hamlett, Cynthia Manning

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Hay, Kenneth W.

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Keim, Kelly

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Kriegel, W. Wurth, and John D. Keys

1935 "Ceramic Materials and Products that have Present or Future Significance in Montana", a radio talk, Montana School of Mines.

Lungren, Waldemar

1933 "Differentiation and Ore Deposition, Cordilleran Region of the United States", Ore Deposits of the Western States (Lindgren Volume), pp. 152- 180, American Institute of Mining and Metal Engineering.

Lyden, Charles J.

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Pardee, Joseph Thomas

1933 "Placer Deposits of the Western United States", Ore Deposits of the Western States (Lindgren Volume), pp. 419-450, American Institute of Mining and Metal Engineering.

Pirsson, Louis Valentine, see also Cross, 324 and Weed, 1791, 1792, 1793, 1795, 1796, 1797, 1798, 1805, 1815.

1897 "On the Corundum-Bearing Rock from Yogo Gulch, Montana", Am. Journal of Science , 4th ser., Vol. 4, pp. 421-423.

Pratt, Joseph Hyde

1897 "On the Crystallography of the Montana Sapphires", Am. Journal of Science, 4th ser., Vol. 4, pp. 424-428.

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1906 "Corundum and its Occurrence and Distribution in the United States," U. S. Geological Survey, Bulletin 269.

Robertson, Almon F., and Robert N. Roby

1951 Mines and Mineral Deposits (Except Fuels), Judith Basin County, Mont. Information Circular 7602. United States Department of the Interior, Bureau of Mines.

Rowe, Jesse Perry

1909 "Development of Montana's Sapphire Mines", Min. World, Vol. 31, No. 19, pp. 921-923.

Sterrett, Douglas Bovard

1908 "Development of Montana Sapphire Industry", Min. World, Vol. 29, pp. 483-485.

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Swallow, G. C. and J. B. Trevarthen

1890 Reports of the Inspector of Mines and Deputy Inspector of Mines for the Six Months Ending November 30th, 1889. Journal Publishing Company, Helena.

Swallow, G. C., J. B. Trevarthen and Jacob Oliver

1891 Reports of Inspectors of Mines, State of Montana, year ending November 30th, 1890. Journal Publishing Company, Helena.

Swindlehurst, J. W.

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Trevarthen, J. B., and G. C. Swallow

1889 Reports of the Inspector of Mines and Deputy Inspector of Mines.

Weed, Walter Harvey and Pirsson, Louis V.

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Weed, Walter Harvey

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Wolle, Muriel Sibell

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Work Projects Administration (WPA), Mineral Resources Survey

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