VIRTUAL FIELD TRIP TO THE KEWEENAW PENINSULA, MICHIGAN - MINING HISTORY (1880-1920)
The mining of copper in the 1880's became even more of an industrial enterprise when the conglomerate lodes and amygdaloidal rocks were mined. Even though these were of lower grades, efficiency improvements in mining made the recovery of copper from these rocks economic. The Quincy mine was being worked before this period and was the first mine to be successful in mining these lower grade ores. These rocks provided a more predictable source of copper ore than were available in the fissure mines. Around 1900, advances in mining technology, and the professionalism of the mine management had made the job of mining into one that could be handled by relatively inexperienced laborers.
The history of copper mining in the area is intimately tied into the Calumet and Hecla company (C&H). This was the largest mining company in the area and produced the bulk of the copper mined. If the dividends paid by the Calumet and Hecla were not included in the totals, the investors in mines in the district would have just broken even. In the early part of the 1900's, production in the district was controlled by four groups of investors from the eastern United States. Calumet and Hecla was run by Shaw and Agassiz which controlled 40% of production. Paine and Stanton ran Copper Range with 30%, Bigelow ran a number of mines which produced 20%, Mason was the primary stockholder in the Quincy Mine which produced 10% of the total district production.
Prior to 1880, all the drilling was done by double jacking. This required a team of two men, one holding and turning the drill tool while the other hit it with a six pound sledge hammer. The short holes ( usually three feet or less) were loaded with black powder. The transition from hand drilling to the use of compressed air drills went smoother in the Keweenaw than in many other mining districts. The mine owners made it economically advantageous for the miners to use the air drills and phased them in over a period of twenty years. Oftentimes in the more economically marginal areas of the mines, the cost of running compressed air lines exceeded the costs of hand mining, so mining was still done by hand drilling. There also was less of a problem with silicosis in the miners than in many other districts. The use of cooling water incorporated into the drills lessened the dust problem that was experienced when the drills were first used. The mines initially converted to some Rand drills which required two men to operate. When the owners converted to one man drills from Ingersoll-Rand, the miners did not want to use this technology.
The Cornish miners were the first major group of immigrants to come to the mines and their experience in mining soon led them to control much of the mining operations. In Cornwall in the 1700's, there had been much advancement in the art of mining as deeper workings led to greater use of steam power for hoisting and pumping. The advent of black powder for blasting the rock also changed the nature of mining. The Cornish industry had relied on the miners as independent contractors. On the day of the "set", mine managers put the work out for contract bidding. There were two types of mining "tutwork" - which was the sinking of shafts and drifting through unproductive rock, and the mining tributors - who mined the ore from stopes. Success in mining required that the miners be able to do up to six months of work and decide how much they were able to bid to get the work done and make a profit. The adventurers had to be able to get a rough idea on the tenor of the ore, how much it would cost to mine and sort the ore, and what the ore would bring in profit since they were paid a percentage of the value of the ore. This created a group of highly skilled miners who understood a broad range of topics on the issue of mining. During the mid 1850's there was a severe depression in the mining industry in Cornwall, so many miners emigrated to Canada and the United States. The miners typically had to pay for the supplies used in the mining process; candles, powder, fuse, and drill steel.
Hoisting rock from the mines usually began as a man powered operation. Two men could lift 1-2 tons of rock from a depth of 100 feet per days work. When the mine grew to a larger size, horse powered whims were used to raise the rock from the mine. Most mines eventually converted to ( and ones with big plans started out with) a steam powered hoist to raise the rock to the surface.
Initially, there was a lot of handling/sorting of rock in the combination shaft/rock house. Over a period of time, this operation became more efficient as gravity was used to replace muscle power. As the ore was brought to the surface, waste rock could be dumped in an area where it was taken directly to the waste rock dump. Ore would be dumped over two grizzlies ( grates made with iron rail). The largest rocks ( which would not fall through the grate) would be fed into a large Blake jaw crusher. The output from this crusher plus the rejects (oversized pieces of rock) from the second grizzly would be fed into a smaller Blake crusher. The material from this crusher and the material that went directly through the two grizzlies would go into an ore bin. Ore was gravity fed from the ore bin into railroad cars for the trip to the stamp mill. Any large pieces of native copper would be run through a large drop hammer to remove any country rock and was sent directly to the smelter. As time went on, the miners tried to keep from having to hoist waste rock and tried to dispose of it within previously mined areas (stopes) underground ( it also helped to support the mine openings).
The first trains in the area were constructed in the 1860's to connect the mines with the stamp mills and supply docks. In the mid 1880's the first trains from the Midwest were connected with the local tracks and the isolation in the winter was lessened.
The mills primarily used stamps for crushing the ore and separating the copper from the rock. They did try to use roller mills to break the ore and although they were more efficient at breaking the rock, they were also more prone to breakdowns. Initially, Cornish stamps (basically a large mortar and pestle) were used. These featured cams to lift the stamp head and used gravity for the drop force. Later steam stamps were developed which directly connected a steam driven piston with the stamp head. This allowed steam to power both the lifting and the dropping of the stamp. Where the first stamps could process 1-2 tons of rock per day, the steam powered stamps eventually could break up to 750 tons of rock per day.
Over the winter of 1913, the Quincy mine converted to one man drills. During the winter there was less union agitation. When summer came, there was a massive strike as the mine owners attempted to introduce the new technology and fire workers. There had been relative labor peace in the district, but these developments led to an increase in membership in the Western Federation of Miners. From a start in November, 1908 the union membership had grown to 7,000 members by the summer of 1913. The strike started on July 23, 1913, but by the middle of August some mines were back in operation. On December 24, at a party given for the children at the Italian Hall in Calumet, someone yelled out "fire", causing a stampede and the deaths of 74; 60 of them children. The strike was over by April 1914. Many of the miners left the area and moved to Detroit to work for Ford in the automotive industry.
Like many other occupations such as cowboys with rodeos and lumberjacks with logrolling and sawing contests, miners also competed in contests of their skills. The primary contests were for rock drilling, either single jacking (one man) or double jacking (two man teams). The judges imported Vermont granite and timed the drilling to a particular depth. Muckers (men who shoveled the broken pieces of ore into mine cars for transport to the shaft) also competed in contests (they would shovel a couple of tons of rock from a 6x3x2 foot bin). The town's social life revolved around a number of fraternal organizations, fire companies, and ethnic religious groups.
Copper miners drilling contest of 8/30/1912 between Calumet and Butte, Montana miners. The miners are using air drills on blocks of granite that are approximately four feet thick. They are using wooden frames to provide support for the drills (active drilling on left station). Photo courtesy Michigan Technological University archives and Copper Country Historical Collections Reeder negative Z 796-A.
A mine near Hancock.
Red Jacket shaft house, Calumet. This shaft was unusual in that it was vertical instead of inclined (these followed the dip of the ore bearings beds). This mine shaft was sunk to mine an area of the Calumet mines and keep it separate from their other mines in the area. Fires had closed the main C&H mines for significant periods of time, and this shaft was an insurance policy against complete production loss due to fire. There were specialized skips for removing rock from the mine, taking men into and out of the mine, taking supplies and equipment into the mine, and for dewatering the mine ( some mines did use pumps for this purpose, but the drier mines could use a skip for water removal). Some of the original and smaller mines used horse powered whims for hoisting, but most operations relied on steam to power this equipment.
Miners on mancar just up from the Quincy mine. The shafts were inclined so that a mancar rather than a cage ( like an elevator - used in vertical shafts) were used to take miners down into the mine. Miners used candles or oil lamps to provide light underground during this period ( later, they used carbide or electric lamps). Time was transition from "soft" hardhats to more rigid ones. The candles were often attached to the hats with clay.
This is a drift in the mine. Note the large size of the timbers supporting the roof of the mine. The mines reached a vertical depth of 6000 feet and large timbers were necessary to support the large pressures wanting to close the openings. The angle of the back (roof) follows the dip of the ore bodies in the mines. Trammers would push ore carts along the rails between the stopes where the ore was being mined and the shaft (it was cheaper to hire men to push the ore carts rather than using mules or locomotives).
Portage Lake Foundry and Machine shop, Sheldon, Wanger & Cleves, Proprietors.
Mills such as this were often built into hillsides. Gravity is used to feed the
ore through the various processes. Ore was brought to the mill by train (1) and dumped
into the building (2). It then was shoveled into the steam stamp (3) to reduce
the ore to a size of 1-2mm. Steam was generated by a boiler (4) that provided
power to the steam stamp, to a stationary steam engine (5) that provided all of
the mechanical power for the mill, and a water pump (6) to provide the water
needed for the processing. Power from a stationary
steam engine was distributed throughout the plant via leather belts and pulleys.
Ore from the stamp was then processed by jigs (7), which concentrated larger
pieces of copper that had not been reduced in size by the stamp (copper is
malleable, and larger pieces would not be decreased in size by the stamp). The
separation of the sand sized particles of ore was done on a sand wheel (8). This
also allowed the copper to be separated by the difference in specific gravity
between the copper and the waste rock. The concentrate of copper ore ( which
would run about 60% copper was then loaded into barrels (9) for shipment to the
smelter, while the waste rock was disposed into one of the lakes (10). This
processing led to losses of about 25% of the copper originally contained in the
ore. This method was not very efficient in concentrating copper if the copper in
the ore occurred as small grains. Later, the more efficient Wifley tables were
used to replace the sand wheel. Photo courtesy Michigan Technological University archives and Copper Country
Historical Collections. Negative 02708.
Tamarack stamp mill. The ores were crushed by the stamps and concentrated on the inclined tables (Wifley tables). Note the barrels that were used in shipping the ore.
The ore processed by the stamps consisted of rocks up to 3 to 4 inches in size. As the stamps pulverized the rocks, when the size reached 3/16 of an inch, the material passed over the tables that used gravity to separate the copper from the rock ( native copper is much heavier than the volcanic rocks making up the gangue). The mined ore grade was between 1 and 5 % copper. Most of the mines constructed stamps on the shores of the lakes in the area where they would have access to water, a place to dump the waste rock sands, and easy access to shipping to the outside world. Various methods were used to separate the copper and waste rock. They all relied on the difference in specific gravity between the copper and waste rock to separate them. The output of this process was to get the copper concentrated to 60% of the ore.
Smelter at Houghton. In the district, the smelter (a high temperature furnace) was used to separate the native copper from the rock in which the ore was found. The concentrated ore was heated in the furnace until the ore became two immiscible liquids. The liquid copper is heavier than the liquid silicate melt that the rest of the ore formed. By tapping the furnace on the bottom, the copper could be drawn off while the silicate melt could be drawn off from the upper portion of the furnace.
Refinery. The smelting operations were primarily concerned with separating the native copper from the rock the ore was found in. Unlike other smelting operations which were required to free the copper metal from chemical compounds, this operation was used to reduce the amount of silicate rocks in the metal. The copper was melted and poured into molds to form ingots, which were a convenient way to ship and sell the copper.
The ingots from the Isle Royale Mine in Houghton were loaded aboard steamer Juaniata for shipment on the Great Lakes for further refining and fabrication. The copper from the district was known for its purity and much of the copper found its way into the wire that was used for the electrification of the U.S. The Great Lakes were closed to navigation between November and May, so the entire years shipping had to occur during this period.
Copper replacing fire brick (15 cm across). Sample is from Calumet and Hecla smelter at Hubbell. Fire brick was used to line the smelter furnaces to help protect the furnace from being melted. Over time, the copper partially replaced the minerals in the fire brick. This material has been used as a lapidary material in the area.