EDITOR’S NOTE: We continue this week with part two of a series on the history of the Iroquois Mine. The first part of this series was published in our Feb. 22 Mining edition. Watch for future installments in upcoming editions of the Hometown Focus. – Kirsten Reichel, HTF Staff Writer
How a mill mine works
The process of mill mining (milling) is very unique. The overburden is stripped off the ore body. A shaft, along with necessary apparatus equipment, is sunk next to the open pit and goes as far down as to reach below the ore body to be mined. Tramways are then dug from the shaft out under the ore body. In-mine shafts (the mills) are dug in from the top of and through the ore body, down to the tramways under the ore body. Either by manual hand shoveling, mechanical cable scraper, or small power scoop shovel, the iron ore is dropped down the ore body shafts (mills) to small bins or ramps. The iron ore is then flowed into tram cars.
The loaded tram cars are moved by a tram to the shaft to be unloaded into a skip. The skip is hoisted up the shaft to then be dumped directly into waiting railroad iron ore cars, or dumped into a waiting small ore haul car(s) which then travel across a trestle, on its own narrowgauge track, from the head frame to a stock pile area where the ore is dumped. Later, that iron ore is loaded into railroad iron ore cars that we have all seen.
This system of mining may seem overly complicated and inefficient. It worked well in confined areas, or when the iron ore being mined fetched high prices. Other Mesabi Iron Range mines that used the milling process to remove iron ore were the Sharon Mine in Buhl, the Albany Mine in Hibbing, and parts of the Fayal, Adams and Leonidas Mines in Eveleth, plus some small, low-tonnage operations.
Something appears to be different about the Iroquois Mine milling operation. If one looks closely at the presented photo of the almost pumped-dry Iroquois Mine, there appears to be only one large mill towards the north end of the mine. The mill appears to line up with the shaft on the west mine bank. Maybe this mine had only one mill, while other Iron Range mill mines had several mills.
The mined iron ore was shipped by rail to the Duluth-Superior ports by the Duluth Mesabi & Northern Rail Road (DM&NRR) and possibly, towards the end of mining, also by the Great Northern Rail Road (GNRR). The first rail route was from the mine site, south-westerly, to the now present Canadian National track south of the downtown area. If one knows where to look, that first rail grade can be seen on the east side of Mineral Ave., now almost covered by the south waste ore rock dump, some 100 yards north of the city recycling center.
A second route connected up to a later east-west Great Northern rail line and later to a parallel west-bound Duluth Mesabi & Northern rail line. At the same time the milling operation was going on, additional iron ore was being underground mined to the north the open milling pit via adits dug in the mine wall. That was the way things went until the mine closed down at the end of the 1914 ore shipping season.
The following is what was left after the mine closed down. The rail grade to the stripping dump to the south was mostly covered by rail main and passing tracks of the GNRR, which ran from east of Virginia to the west end of the Mesabi Iron Range and beyond. The north underground mine via adit area eventually slumped and created a several-acre 20-foot-deep valley with a 10-foot deep pond. Many from the area can still remember that pond since it remained until 1957 and was a place to go catch some nice pan fish.
Some funnel-shaped water-filled slumps were present next to a short street east of and parallel to Mineral Ave. Those slumps had minnows that were trapped by locals for regular lake fishing. The mine mill area, 500-feet wide by 1000-feet long and averaging 150-deep, filled with water, but not to the top. There was no approach down to the mine water and, since it had 30-degree vertical banks all the way around, no swimming took place as was the case in other closed down mines.
The mine rail yard tracks were removed and the area grew over with tall grass. The south stripping dump grew over with poplar trees, with a few large pines mixed in. A W-shaped 36-foot tall lean ore stock pile remained next to the alley on Mineral Ave. and became covered with small trees. A 20-foot tall cone-shaped pile of shipping grade ore was a few feet south east of the lean ore stock pile. All the mine buildings and coal trestle were removed.
The shaft, with a large diameter pipe in the center, caved in somewhat and filled with water. Foundations of the engine-hoist house, water tank and boiler house remained. A full block and another quarter block of homes remained at the Iroquois location. And that’s the way it was for 42 years until the fall of 1956.
Ed Roskoski lives in Mt. Iron, MN.