Like the office building, the library was designed by Shaw and Hunnewell.
 The building is two-and-a-half stories high, built of rough masonry trimmed with brick around the windows, and with brick quoins.
 It is built in a "T" shape, with the main wing measuring 62 feet (19 m) by 42 feet (13 m) and the south wing 38 feet (12 m) by 32 feet.
 The roof is formed from two intersecting gables covered with dark grey slate.

The building was originally designed to house adult and children's reading rooms on the second floor, library stacks, office space, and cloakrooms on the first floor, and baths for men, women, and children in the basement.
 Small alterations were made over the next few years, including adding a west entrance porch, reconfiguring the baths, and adding more shelves.

In 1911, a new bathhouse was constructed, and the bath section of the library was remodeled to provide additional stack space.
 However, as the fortunes of the Calumet & Hecla Mining Company declined, support for the library became difficult.
 In 1944, the library collection was transferred to the Calumet High School, and the building was converted to office space.
 The library currently serves as the Keweenaw History Center, housing historical artifacts and archives.

The library is significant as a notable example of the paternalism of corporations at the time, as well as being a striking example of sophisticated design and stonework.
Like the office building, the library was designed by Shaw and Hunnewell.  The building is two-and-a-half stories high, built of rough masonry trimmed with brick around the windows, and with brick quoins.  It is built in a "T" shape, with the main wing measuring 62 feet (19 m) by 42 feet (13 m) and the south wing 38 feet (12 m) by 32 feet.  The roof is formed from two intersecting gables covered with dark grey slate.
The building was originally designed to house adult and children's reading rooms on the second floor, library stacks, office space, and cloakrooms on the first floor, and baths for men, women, and children in the basement.  Small alterations were made over the next few years, including adding a west entrance porch, reconfiguring the baths, and adding more shelves.
In 1911, a new bathhouse was constructed, and the bath section of the library was remodeled to provide additional stack space.  However, as the fortunes of the Calumet & Hecla Mining Company declined, support for the library became difficult.  In 1944, the library collection was transferred to the Calumet High School, and the building was converted to office space.  The library currently serves as the Keweenaw History Center, housing historical artifacts and archives.
The library is significant as a notable example of the paternalism of corporations at the time, as well as being a striking example of sophisticated design and stonework.
Calumet and Hecla Industrial District