IndustryQuincy Smelting Works

The Support Buildings (p3)

While most of the Quincy Smelters support buildings run along a line at the facility’s west end, a few others are scattered randomly about the rest of the property. Two of the more prominent of these structures are on the facility’s south end, sandwiched in between the coal and copper docks. These minor players on the Quincy smelter stage are the Assay Office and Charcoal House.

Here’s the two buildings in question, as photographed back in the late 70’s. The Assay Office is to the left, while the sandstone Charcoal house sits to the right. While the Assay Office has held up well over the years the Charcoal House was not so lucky.

As it sits today the Charcoal House is just a set of sandstone walls, its wood frame roof succumbing to the region’s harsh winters long ago. Even without the roof the building is still impressive, especially considering its role as a simple storage facility. Charcoal used by the Cupola furnace would have been stored here until needed, delivered off of ships docked at the coal dock next door.

Built in 1898 the Charcoal House features the same sandstone beauty and architectural detail found throughout the smelter’s original compliment of structures. That includes the staggered sandstone quoins on the structure’s corners.

Making our way behind the Charcoal House we find this odd item attached to its backside. Erected out of concrete this waste high “wall” looked like the foundation for an addition to the building. Except this foundation was capped by several large iron “brackets” running along its length.

Here’s another look at these “brackets”. I would guess that these were used to attach some type of skeletal structure to the foundations top, an assumption that led me to believe that we were looking at the remains of some type of storage bin.

From this HAER photograph it looks like I was correct. Here you can clearly make out the same foundation I photographed at the site, but at this time its upper structure was still intact. According to old Sanborn maps this particular bin was used to store sand, sand which was used to line the bottom of the reverberator furnaces I would guess. Originally, when the Charcoal was built the sand house was a separate building, but for some reason the two buildings were later joined as one.

Feeding both buildings was an overhead trestle, which dumped the sand down into the sand bin and into the Charcoal House from its attic. Though the trestle is missing in this particular photo, you can make it out – just barely – as it enters the top of the Charcoal house in the very first photo featured on this page.

Next door to the combo Charcoal / Sand House is out second building of the day – the Assay Office. Essentially a small chemical laboratory, this building was used to test the purity and general condition of the copper coming out of the furnaces.

Here’s the laboratories backside. The original structure (on the left) was one of the complex’s original buildings, built on this spot in 1898. In 1908 it was expanded and upgraded, resulting in the addition to the right.

This particular building featured its own brick chimney, for what I assume was the building’s furnace. But it’s the only building on the property to have such an amenity, which makes be think that it was perhaps used for a different purpose (perhaps a crucible for melting copper samples?). I would have assumed that this building like all the rest was heated by steam provided by the boiler houses. But perhaps this building was off the grid so to speak and required its own heating equipment.

The Quincy Smelter is private property and is open to the public only during special Quincy Smelter Association’s tours and events.

To learn more about the assay office and charcoal house be sure to visit the Quincy Smelter Blog for their own virtual tour of the site.

To view more photos from the Quincy Smelter – including some awesome wide angle imagery – be sure to check out the Quincy Smelter Gallery at David Clark Photography!

And of course, if you have any photos of your own to contribute to the discussion, make sure to post them over at the Copper Country forum’s Quincy Smelter Thread.

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  1. the Chimney was probably for at least back up heat and Fire Assay’s, of course when your assaying you may not need heat! I imagine that this is one building you would not want to freeze in the event of a boiler failure due to the analyitcal chemicals, etc housed there.

  2. Something funny on the assay office roof. look at the 2nd to the last photo on this page. There is a steel vent stack exiting the roof on either side of the ridge but look at the one on this side of the ridge.
    There’s a flashing, then no pipe for 4′, and the top of the stack in mid air! You can see the same thing in the 2nd b&w photo near the top of the page.
    If I look real close at my screen I can see a guy wire coming off the brick chimney on the left that must go through the top of that stack. It’s funny that it could hang like that for over 30 years!

  3. Louis, charcoal was not the primary fuel used in the smelter. Coal was and there was a large coal dock and storage area on the site. Charcoal was sometimes blended in to affect the properties of the smelt and was probably used in the assay office crucible and any forges at the smelter. As large as the charcoal house is, it would not be sufficient if charcoal was the only fuel used in the smelter.

  4. The charcoal may have also been used to de-oxidize the molten copper. Traditionally a chunk of pinewood was tossed in to burn off oxygen in the molten metal; they probably progressed to a more refined charcoal instead of plain wood. I still use the process today when casting jewelry, just on a much smaller scale. The wood or charcoal burns off instantly using the oxygen in the metal for combustion; what remains floats on top and is skimmed off with the slag.

  5. As an MTU grad with a degree in metallurgy who spent a lot
    of time working with melting of copper base alloys including pure
    copper, the charcoal was used to cover the surface of the molten
    metal to prevent absorbtion of oxygen. Pure copper has a very high
    affinity to absorb oxygen from the atmosphere. Charcoal is pure
    carbon and provides a layer to block exposure and is essentially
    insolube in molten copper. Poling with logs was used in
    reverberatory practice at the time, but not purely for removing
    oxygen. It provided a mixing fuction by boiling off the moisture in
    the wood below the surface of the molten metal to generate a
    uniform composition. A reverberatory furnace is essentially a dead
    melt and impurities can stratify. They also used the logs to push
    the floating impurities or slag to where it could be taken off the
    surface prior to pouring the ingots. Steel is used now for this
    function, but wood was cheap and readily available. There is no
    stirring action in a reverberatory furnace such as created by the
    magnetic field in current technology induction furnaces that would
    bring lower density impurities to the surface where they could be
    removed with the slag. Deoxidation of copper and its alloys is
    currently done with the addition of phosphorus as an alloyed
    copper-phosphorus shot. A product not available at the turn of the
    last century.

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