A hemostatic device for promoting the clotting of blood includes a gauze substrate, a clay material disposed on the gauze substrate, and also a polyol such as glycerol or the like disposed on the gauze substrate to bind the clay material. When the device is used to treat a bleeding wound, at least a portion of the clay material comes into contact with blood emanating from the wound to cause the clotting. A bandage that can be applied to a bleeding wound to promote the clotting of blood includes a flexible substrate and a gauze substrate mounted thereon. The gauze substrate includes a clay material and a polyol. A hemostatic sponge also includes a gauze substrate and a dispersion of hemostatic material and a polyol on a first surface of the substrate.