This safety helmet was used while working underground at Cornwall Ore Mine.
Safety helmet, brown textured coating on the exterior; short brim; black plastic lamp bracket above brim; short plastic strap with snaps riveted to rear exterior of helmet; interior suspension composed of plastic and woven synthetic fibers (probably nylon); suspension is attached to the helmet via 4 metal clips; underside of brim is stamped "MSA"
MSA [Mine Safety Appliances] Inc., originated in Pittsburgh, PA. The company originally specialized in mine safety, but has since expanded to other industries.