MinesSeneca Mine

A Short History Of Seneca

The Seneca Mine began its life during the Copper Country’s adolescence – around 1860. Before then most mines across the peninsula were duds, lit off by excited investors only to fizzle away into nothing. Interest began to fade and new mines were slow in coming. But thanks to the unprecedented success of the Cliff, investors suddenly discovered a new found interest in the region. A new wave of mines began to spring up, a great deal of which set their sites along the rugged bluffs of the Cliff Range – the same formations along which the Cliff had found its own fortunes. One of the largest of these new mines was the Seneca, an endeavor whose namesake was one of the Five Nations – a coalition of native tribes that once dominated the region occupied today by the state of New York.

The Seneca acquired nearly 3000 acres of land stretching over three miles along the Cliff Range. The owned most of the land that sits between the present day town of Ahmeek on the southern end and the Ojibway Mine to the north. Early work concentrated along the Greenstone, which was encased within the rugged bluffs that form the Cliff Range. Like most mines of the day, all hopes were attached to the discovery of a copper-rich fissure vein such as the one found at the Cliff. Towards that end the company focused its efforts along the Cliff Range’s southern most extension – a knobby outcropping or rock sitting alongside what is known today as Seneca Lake.

Subsequent explorations resulted in the discovery of the Seneca Vein – a small and narrow copper fissure that the company hoped would yield results. A small surface plant was hastily erected and a shallow shaft and adit were driven into the newly discovered vein. While work progressed adjacent land was cleared and the humble beginnings of a townsite took shape. The small town was made up of just a few log dwellings, smith shop, stable and agent’s house. A few more buildings were built down at the lake itself and a road cleared towards the mine site. The total workforce at the time was just six men.

Unfortunately the Seneca vein turned out to be a dud, and the company searched elsewhere for their elusive prey. In the following years the company would turn their attention to finding outcroppings of bedded lodes across their property, including the Allouez and Calumet lodes. In 1880 the company set off over 900 acres along its southern property to form the Ahmeek Mine, while work along its northern frontier was halted. It wasn’t until the mine received a new influx of cash – in the form of majority investor C&H – that explorations were continued. This time the company turned to finding the copper rich Kearsarge lode from which its neighbors (the Gratiot and the Mohawk mines) were mining with some success. By 1908 that lode was discovered on the mine’s eastern-most lands and a shaft was quickly sunk to exploit it. Finally it looked as if the Seneca had found its paying lode.

But things would once again turn sour for the company as its Kearsarge shaft began to run out of room to mine the lode profitably. The lode outcropped along only a short section of the company’s land, and the neighboring Gratiot Mine had chocked off most of the lodes upper levels from development by Seneca. There were only two options available to the mine if it were to stay in business. First it could buy out the neighboring Gratiot Mine – freeing up their lodes upper levels and providing much needed breathing room. Or it could attempt to mine the lode at depth, sinking a shaft straight down until it hit the lode and moving on from there (in much the same was as the Tamarack attacked the Calumet conglomerate). Unfortunately both options involved a great investment of capital – an investment that C&H was apparently unwilling to make. The mine was shut down in 1911.

But internal squabbles would result in another turn of events. Unhappy with C&H’s majority stake in the company in lieu of its decisions regarding the mine, a concerned group of investors worked to wrestle control away from the mining giant and regain full control of the company. By 1916 that goal was finally realized and C&H’s stake in the company was bought out by the Seneca Copper Corporation. The mine was re-opened and the newly minted company worked to relieve those space mentioned earlier; by sinking itself a new shaft in 1918. This new vertical shaft – known as the Seneca No.1 – dropped over 1400 feet down to the buried Kearsarge Lode and proceeded to mine it at depth.

Buoyed with a newfound optimism (and some extra cash), the Seneca Copper Corporation turned to buying up its rival to the east – the Gratiot Mine – in 1919. The two shafts of the Gratiot were added to the Seneca’s surface plant and became shafts No.2 and No.3. The company would continue to work these shafts for another half a decade, producing some 3 million pounds of copper before all was said and done.

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  1. A few interesting notes about the Five Nations and its connection to copper country naming conventions. The coalition was more widely known as the Iroquois League (also a name of a nearby mine). Along with the Seneca the league also featured the Mohawk (also a mine) and the Oneida (one of the Delaware’s long list of names). Most interesting is the fact that one of the more famous members of the Seneca tribe was a man by the name of Red Jacket, who worked closely with the British to insure peace and Seneca sovereignty. He was given a red coat by the British, and the name apparently stuck.

  2. Hi Mike, I just want to verify a point of reference for myself. On the second map above, is the Seneca 3 shaft the one that presently today has the bat cage that you can see off of 41? Thanks.

    1. It is the one with the bat cage over it. It was originally the Gratiot No. 1 shaft.

  3. That verticle shaft was also built to get a lot of rock to the surface. I read it was built to handle 5000 tons of rock a day.

    Seneca Copper lasted until December 1930. When Seneca purchased the Gratiot, they connected the Seneca #1 with the Gratiot/Seneca #2 on the 25th level, although they broke through in the Seneca shaft, they never finished it.
    C&H bought the Seneca property back in December 1945.
    C&H started working on reopening the #2 shaft in May 1946.
    C&H eventually connected the Ahmeek #4 shaft and the Seneca #2 on the 30th level. They drifted from Ahmeek #4 then drove a raise up from the drift to intercept the #2 shaft, when they did they were right on with the connection.
    May 1947, they were still working on rehab of the shaft along with installing the new surface plant.

  4. Didnt C&H begin production at the “remodeled” Seneca #2 (A.K.A. Gratiot mine) in 1948? I remember reading that somewhere, as well as i recall the shaft being the last major installation of a steam engine in the Keweenaw… C&H transferred the hoist engine from one of their defunct shafts on the Calumet Conglomerate lode…. Either way the shaft ended up lasting into the 1960’s.

  5. Ian, that is what I heard years ago from a gentleman (Irv Peters?) who had worked for C&H while the rehab was in progress. I can’t recall which shaft he said the hoist came from other than it may have been one of the Osceola shafts. By that time C&H was very good at recycling equipment. One of the best examples of that was the installation of one of the Tamarack 5 hoists at Ahmeek 3 in the late 1930’s. The glory days of Agassiz buying things in duplicate were long gone.
    They were quite innovative, he told me they used a 25 ton railroad crane to string power and telephone wires, along the ROW. They ran the wires over the top sheave of the crane and laid them on the crossbars of the poles. He said they started this practice during the Seneca project.

  6. They used a temporary hoist from Centenniel to start the project.
    The permanent hoist was from the original Osceola #13, both the hoist and the hoist building were moved to Seneca. Every thing at Seneca was scrapped. The hoist from Osceola was good for 6000 ft and handled 2 skips in balance of the 8 ton variety.
    Kind of interesting how almost everything else at the shaft was electric, except for the hoist.
    Some production was actually done with the rehab, but that was mostly on account of the rehab. 1948 would be about right for the start up. I haven’t scanned the later News and Views I have, May 1947 is as far as I have gotten. Wasn’t to many more issues from what I remember, economic downturn caused the price of copper to drop, C&H shutdown everything until things picked back up.

    The December 1946 C&H News and Views has a photo of them stringing wire with the crane, at the time it was between Calumet and Lake Linden, an electrical foreman came up with the idea, they used a 3 pulley snatch block on the boom of the crane, put the rolls of wire on flat cars, raised the boom over the arms on the pole and off they went to the races. With a locomotive pushing the works, 1mph.

  7. I went through the rest of News and Views, from what I gather, they were already mining on a limited scale in 1947 while they were still rehabbing. The former Osceola hoist was installed and in service in May 1947. They were using a temporary electric air compressor until the two new permanent compressors arrived.

    In the March 1956 Red Metal News, they showed on the 21st of March, a record 1928 tons of rock was brought to the surface, 266 skips to the surface that day, I think that would be about a skip every 6 minutes or so.
    Cable must have been really singing that day.

  8. i have just found a certificate for 50 shares of seneca copper mining co. that my uncle bought on march 30, 1942….is this worth anything? or should i just frame it for the wall?
    please let me know….thank you, frank and sandy bertog

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