This photograph of the Monson-Maine Slate Company's Monson quarry depicts the depth and sheer walls of the open pit mining.

This photograph shows three men on the pit boom and hoist beam above the open pit. Levels of slate slabs were used to shore up the sides of the pit to make it level for the buildings and hoister operations. These various levels of slate slabs as can be seen from the "seams" along the sides of the sheer face of this operation. In the background is the processing mill, which was sold to Moosehead Manufacturing Company in 1947 and, as of 2012, is abandoned.