Hello, my name is Jacob. I have a good amount of quality (blue) slag glass from the heart of iron mining in the Great Lakes region. The furnace in which my material comes from dates back to 1857. To be specific, The Jackson mine (Negaunee, MI) was the first iron mine in the Great Lakes region. In 1857, the first furnace was built adjacent to the mine, only to burn down in 1874, causing widespread panic amongst the growing city of Negaunee. About a year after the furnace burnt down, the mines reopened and started shipping their ore out to furnaces like the ones in Frankfort, MI and Fayette, MI.
Originally, I donated a display set to the local museum and in return received confirmation as to which furnace produced my pieces of slag. From that information I have rigorously searched the internet for as much detail on the history of the material. Although quite vague, I was able to find some information as mentioned within this post. I have attached three links to my main sources of information on the history of the material. Also, I have attached some photos to showcase some of my material. If interested, please message me here by comment or preferably by E-mail. jfiggs116@gmail.com
Sincerely, U.P.SlagDistributor

Sources:

Brennan.J. (1957). Marquette Iron Range. Retrieved (2017, Sept. 20) from <http://www.michmarkers.com/startup.asp?startpage=S0035.htm>

Fuller.G.N. (1873-1957). Pioneer Furnace. retrieved (2017, Sept.20) from <http://genealogytrails.com/mich/marquette/businesspioneer.html>

Swineford.A.P (1876). History and Review of Copper, Iron, Silver, Slate and Other Material Interests of the South Shore of Lake Superior (pg.120). Retrieved (2017, Sept. 20) from <https://books.google.com/books?id=-IFBAAAAIAAJ&q=120#v=snippet&q=120&f=false>

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