The Isle Royale Mine originally opened in 1852, on a section of the Isle Royale lode squeezed between the Grand Portage to the north and the Huron on the south. By 1854 the mine was joined by a small stamp mill, joined to the mine by a 2-mile long tramway. Unfortunately the mine found little success, and was leased on tribute to the Mabbs brothers. They too were ultimately unsuccessful, and the mine closed down by 1882. In the end over a million dollars was sunk into the property – with very little results to show for it.
In 1899 the mine was given a new lease on life, having been bought up along with the neighboring Grand Portage and Huron Mines in the formation of a new mining company – known as the Isle Royale Copper Company. Fueled by a large investment by none other then C&H itself, the new company got to work sinking a new series of shafts in the old Isle Royale Lode – this time with a little more success for their efforts.
Isle Royale No.6 sits on the company’s far southern end, originally part of the failed Frue and Dodge prospects. It was a three-compartment shaft with a depth of about 2,500 feet. Besides the adjacent rock house, the only evidence of the shaft today is the flat slab of concrete used to cap it.
More visible is the remains of the old rock house, which stand nearby. Since the No. 6 was one of the Isle Royale’s more recent shafts, it sported a more modern surface plant. This included a steel and concrete rock house that utilized a large steel rock bin (C) set atop a pair of concrete walls. Between those walls would have ran a line or rock cars (A), filled by means of a series of rock chutes protruding from the bottom of the rock bin sitting above them. The pillar rising up from the ruins (B) was the base for a steam powered rock hammer that once sat above it. The shaft is to the left in the picture (D).
Here is one of the concrete walls, which resembles the letter “D” from above. The weight of not only the rock house superstructure, but the rock bin and its contents as well, would have been supported by this foundation and its sibling to the left.
A closer look at the walls themselves reveals a great deal about how they were constructed. The vertical grooves in the wall are from the form itself, which was apparently built up from several vertical boards strapped together. This is in contrast to the rest of the wall, which is faced with horizontal grooves. In those sections horizontal boards were used instead. You can also see that the wall was poured in three stages, due to the slight change in color and consistency apparent as you move up the wall.
This narrow opening – about a dozen feet wide – was were the ore cars would be run when loading up on copper from above. The picture is looking north, towards the No.5. You can also see in the photo the horizontal grooves along the walls, evidence of the horizontal boards used in the form here.
Fastened into the base of the concrete walls – right at the opening of the ore car corridor – are a series of eye bolts similar to this one. No idea what these were used for, though it must have been used to tie something down to the foundation. (perhaps the cable stands?)
Meanwhile at the north side of the foundation we found these series of holes drilled into sides of the ore car opening. Obviously something was attached to the foundation here, I just don’t know what.
On the foundation’s north-west side is this pillar that supported the rock house’s drop hammer. This “drop hammer” was essentially a large weight that was dropped from great height onto a stubborn piece of rock to free the copper imprisoned within it. Here you can not only see the vertical grooves from the form, but the boards themselves.
Before leaving the old rock house remains, we spotted this interesting piece of concrete laying nearby. Its etched with the date of 1918, which as far as I know isn’t a date of any significance. The shaft was built long before 1918, and the cap would have been placed much later then that. Perhaps the current ruins are from a replacement rock house built around 1918? Or perhaps the things upside down and actually reads 8-1-61?
To Be Continued…