The Scratchgravel Hills are a low range of mountains on the west edge of the Prickly Pear Valley just northwest of the city of Helena. The maximum elevation of the hills is 5280 feet. Mining activities in the Scratchgravel district encompass an 80-year period of major mining developments beginning with the placer operations of the 1860s to World War II.
The first placer mining in the Scratchgravel Hills was reported to have occurred even before the Last Chance Gulch placer deposits were found in 1864. These initial placer deposits in Iowa Gulch on the northwest side of the hills were thin and mined only on an intermittent and small-scale basis. Other placer areas in the hills were also small and scattered. Sizeable nuggets, however, were occasionally found after heavy rains in Butcher Knife Gulch in the northeastern part of the district (Swallow 1891; Pardee and Schrader 1933; Wolle 1963; McClernan 1983). The district had a reputation for placers and veins so rich that nature must needs make them small, and veins so large the gold was not sufficient to make them rich (Swallow 1891:38).
In the south part of the hills the deposits were in a sheet of gravel close to the surface. A farmer named E. R. Tandy plowed a few acres in the area and claimed to have turned up a 27 ounce nugget of gold. Others then plowed and raked the area for more nuggets. It was not recorded what was found but the activity did give the hills their name. Total placer production is not known but it was never very large and it ended within a few years of the initial discoveries (Pardee and Schrader 1933; Wolle 1963).
The northern part of the Scratchgravel Hills is underlain by shale, sandstone and limestone of the Algonkian (Belt) age. These rocks are folded, and adjacent to granite that has altered them to quartz-mica schist and other metamorphic products. The south and central portions of the Hills are composed of quartz monzonite, an intrusive igneous rock that is popularly known throughout the region as granite. The Grass Valley area west and southwest of the Scratchgravel Hills is underlain by Empire shale and Helena limestone of the Belt series. These rocks have also been intruded and metamorphosed by stocks of quartz monzonite. The ore deposits in the Scratchgravel Hills occur in contact-metamorphic deposits and in veins that have filled open fractures. The contact zone deposits include several bodies of magnetic iron ore useful as smelter flux. Chalcopyrite, malachite, and chrysocolla also occur in the metamorphosed contact areas, but no workable copper deposits have ever been located. The vein deposits fall into two groups, gold-quartz deposits and lead-silver ores -- primarily galena (Pardee and Schrader 1933).
Lode mining in the district got underway in the early 1870s and proved to be profitable although relatively short-lived. The first lode mine to come into production in the district was the Lexington which was in operation during the 1870s. It was said to have produced $250,000 worth of silver, lead and gold ore before it closed in 1880. Some of the ore was rich enough to make it profitable to ship it to Swansea, Wales for smelting and refining (Pardee and Schrader 1933; Wolle 1963; McClernan 1983).
Another profitable lode mine was the Franklin located at the southern end of the district. Initial, small-scale lode mining was done on the Sam Gaty and Doctor Steele claims as early as 1870. The property was then acquired by Thomas Cruse, the mining entrepreneur who discovered the bonanza Drumlummon mine at Marysville. Cruse operated the Franklin mine from 1914 to 1918 and produced ore worth nearly $500,000, 90 percent of which was in gold and the remainder in silver (Pardee and Schrader 1933; Wolle 1963; McClernan 1983).
Also operating during this same period was the Scratch Gravel Gold mine located just one half mile southeast of the Franklin. The mine had extensive workings and operated from 1915 to 1918, producing around 6000 tons of gold ore worth $261,000. The Katy operated in the 1910s and 1920s, producing about $75,000 worth of ore. The North Star, although small-scale, was in production longer than any other mine in the district, producing 736 tons of ore in the period from 1901 to 1942, yielding 509 ounces of gold and 7070 ounces of silver. The Cruse Consolidated Mining Company mines included the Helena, Rock Rose (Dandy), and Looby and were operated intermittently for about 30 years from around the turn of the century to their closing around 1927. They were reported to have produced $118,000 in lead, silver and gold ores. Another mine operated after the turn of the century was the Silver Coin which mined a rich vein of silver ore. The mine had more than 400 ft of drifts and crosscuts in the ore body which had assay samples run as high as 1000 ounces of silver to the ton. Some 3320 tons of ore were reported to have been taken from the property (Pardee and Schrader 1933; McClernan 1983).
Other mines of note in the district include: the Aster which had a small amount of production; the Blue Bird Copper and Silver Mining Company mine which was developed from a 175 ft shaft and 700 ft of drifts; the Elizabeth which had a small mill to process the mine's gold ore; the Ella, developed from a crosscut tunnel and drifts; the Golden Crown, which produced and milled a considerable amount of unprofitable gold ore in the decade following 1893; the Moonlight-Hopeful mines, which produced some silver ore; the Julia, which was said to have produced a moderate amount of lead, silver and gold ore; the Magpie, developed from an incline shaft; the Mullin, which had 1000 feet of workings but no record of any production; and the Wayside, Blue Bird, and Nettie claims of J. C. Robinson who produced 200 tons of $40 per ton ore from the Nettie (Pardee and Schrader 1933; McClernan 1983).
A small amount of development work and reworking of old dumps was also carried out up to World War II but virtually no mining activity has occurred since then.
BOUNDARIES OF THE DISTRICT
The Scratchgravel district is a relatively simple entity to define. As Pardee and Schrader (1933) point out:
The Scratchgravel Hills occupy an area about 3 miles wide and 4 miles long from north to south that begins about 2 miles north of Helena. They stand out prominently in the western part of Prickly Pear Valley, and except for a low ridge that extends to the foothills of the Continental Divide on the west, they are completely detached from the neighboring mountains. On other sides they are surrounded by the nearly level floor of Prickly Pear Valley, to which they present an abruptly rising east front (Pardee and Schrader 1933:35).
Both Pardee and Schrader and McClernan (1983) show a similar area in maps of the Scratchgravel district. The district covers an area within:
Sections 13 - 16, 21 - 28 and 33 - 36, T11N, R4W Sections 1 - 4 and 9 - 16, T10N, R4W
HISTORIES OF SELECTED MINES
The Ajax mine is two incline shafts that explore two parallel veins. The veins are iron-oxide stained quartz separated by about 4 or 5 ft of decomposed granite. The shafts were noted to be about 100 ft deep in 1933. Sixty two tons of ore were shipped to the smelter returning $10 per ton, chiefly in gold (Pardee and Schrader 1933; McClernan 1983).
The Aster mine is located on the west side of the Scratchgravel hills about two miles north of Seven Mile Creek. The mine also includes the Drumheller mine and the Howard mine and was the principal workings of the Helena Silver-Lead Mining Company. The development consists of a vertical shaft that was reported in 1933 to be 200 ft deep with levels at 100 and 200 ft. The mine worked a 1.5 to 2 ft thick vein of sheared diorite containing ankerite with minor galena and chalcopyrite. Some "steel" galena assayed 50 percent lead with 10 ounces of silver and $5.00 in gold per ton (Pardee and Schrader 1933; McClernan 1983).
The Blue Bird mine, which consisted of the Blue Bird, Wayside and Nettie claims of J. C. Robinson, is located in the upper part of the valley that lies between the southern spurs of the Scratchgravel Hills. The Blue Bird claim was reported to have a 90 ft shaft with a 40 ft crosscut. The Blue Bird worked a vein of iron oxide minerals with silver and lead values. Ore shipped from the vein netted $49 per ton. The Nettie claim's 178 ft shaft worked a quartz vein that returned 40 per ton in gold. The Wayside was worked through open cuts and shallow shafts (36 and 50 ft.) and extracted ore from quartz stringers (Pardee and Schrader 1933; McClernan 1983).
Bonanza and Guy
The Bonanza and Guy mines were developed by Williams and Steltemeier. The Bonanza was reported to have a 80 ft incline shaft with a 40 ft drive. This mine had a well defined 5 ft vein containing iron oxide minerals, cerussite and galena. The Guy lode was developed through three short adits. The mine worked iron-stained "honey comb" quartz (Pardee and Schrader 1933; McClernan 1983).
The Elizabeth mine of Fred Moratt is on the northeast side of the Scratchgravel Hills about half a mile west of the Great Northern Railway. It was reported to have several shafts and open cuts. The main development, an incline shaft that was stopped by water at 120 ft. The 4 to 6 ft vein contains limonite, manganese oxide and copper carbonate. It also had values of up to $11.50 per ton in gold (Pardee and Schrader 1933; McClernan 1983).
The Franklin mine is on the south end of the Scratchgravel Hills and is about a quarter mile north of Seven Mile Creek. The mine was first developed in 1870 on the Sam Gaty and Doctor Steele claims. The mine then passed into the hands of Thomas Cruse, an important mine developer in Helena and Butte. In 1914 a gold vein was discovered and extensively mined for three years. The mine closed and filled with water in 1919. East Helena smelter receipts indicate that the mine produced $490,333.73 between 1914-1918, making it the district's most productive mine. The mine was reported to have two shafts and numerous adits. The two veins on the property contain gold values in iron oxides and quartz. Below the oxidized zone the ore values are diminished. One of the veins has been explored 1,000 ft horizontally and 200 ft down while the other vein has been explored 400 ft parallel and 300 ft laterally (Pardee and Schrader 1933; McClernan 1983).
The Golden Crown mine is on the summit of the Scratchgravel Hills, on the main ridge just north of the highest peak. The mine was reported to have had a 380 ft incline shaft and an open pit. The quartz vein is about two ft thick and has values of gold and silver. A small lot of ore from the 120 ft level returned $85 per ton mostly in silver. Developed in the decade following 1893, the mine also had small mill. However, the operation was not profitable (Pardee and Schrader 1933; McClernan 1983).
The Helena mine is located a short distance west of Fort Harrison, in an area known as Grass Valley. The mine consists of the Helena, Rock Rose (Dandy) and Looby claims and was worked intermittently from 1899 to 1918 by the Thomas Cruse Consolidated Mining Company. The mine was reported to have produced 3,860 tons of ore with average values of .29 ounces of gold per ton and 14.34 ounces of silver and 13 to 14 percent lead (Pardee and Schrader 1933).
The Katy is on the east side of the Scratchgravel Hills near the foot of the slope. In the early 20th Century the mine was worked intermittently. The owner reported the total production at $75,000. The mine consists of a 175 ft crosscut and a 50 ft stope. Older workings were present at the mine when observed in 1933 (Pardee and Schrader 1933; McClernan 1983).
The Lexington mine was caved in in 1933 when it was visited by Pardee and Schrader. The size of the waste dump indicates that it was once one of the larger mines in the district; it was reported to have produced a quarter million dollars in ore prior to 1880. The collapsed workings extend 500 ft from the portal. The mine worked three successive deposits; ores with copper, gold and silver values were observed on the dump (Pardee and Schrader 1933; McClernan 1983).
The Mullin mine of Dan Mullen is located on the northeast side of the Scratchgravel Hills. It was reported to consist of an adit 1,000 ft long of irregular course. The mine was working a two ft contact zone that contained values of gold (Pardee and Schrader 1933; McClernan 1983).
The Nettie mine was reported to have several open cuts and an incline shaft 178 ft deep. A thin quartz vein contained 2 ounces of gold per ton. Production for the mine was recorded at 200 tons of ore ( McClernan 1983).
The Scratchgravel mine is located about half a mile southeast of the Franklin mine. It was reported to have an incline shaft 500 ft deep, 2,500 ft of drifts on the shaft and a second shaft about 1,400 ft west of the incline shaft. The mine produced about 6,000 tons of ore with gold values of 1.5 to 2.5 ounces per ton. Smelter return receipts totaled $261,477.19 (Pardee and Schrader 1933; McClernan 1983).
Silver-Copper Mining Company
The Silver-Copper Mining Company property was reported to have a caved shaft that once was 500 ft deep. The shaft was reported to have a conspicuous headframe and a collar lined with granitic rocks. When inspected in 1933 the dump contained a large amount of ankerite vein material (Pardee and Schrader 1933; McClernan 1983).
Brazier, C. R., editor
1935 Mining Review of Greater Helena Region.
Gidel, Murl A.
1939 "History of Geology and Ore Deposits", Seven Talks About Mines, pp. 10-19.
McClernan, Henry G.
1983 "Metallic Mineral Deposits of Lewis and Clark County, Montana", Montana Bureau of Mines and Geology Memoir 52. Montana College of Mineral Science and Technology, Butte.
Pardee, Joseph Thomas and F. C. Schrader
1933 "Metalliferous Deposits of the Greater Helena Mining Region, Montana", U. S. Geological Survey Bulletin #842, reprint of article in Mining Truth, Vol. 14, No. 10.
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, W. J.
1914 Montana Department of Labor and Industry, 1st Biennial Report.
Wolle, Muriel Sibell
1963 Montana Pay Dirt. Sage Books, Athens, Ohio.