 It was used as a general mine operation center, and also housed engineering and accounting departments.The original building was designed in the early 1890s by the Boston firm of Shaw and Hunnewell; two later additions, architecturally faithful to the original, were designed by the Marquette firm of Charlton and Kuenzli.Of these three sections, the eastern section measures by , the western section by , and the northern section by 35 feet.