A Underground Method of Mining Iron Ore
The angle of dip varies from 15176; to 20176;, and up to 85176; and even 90176;, with the horizon. The ore is rather soft, bluishblack in color, and is a hematite. It varies in thickness from a few inches to one hundred feet, or more. It is mainly Bessemer ore, containing 57 to 63 per cent, of metallic iron, and .03 to .07 per cent, of phosphorus.