The color hardener can be applied using one of two procedures; integral color or cast-on color. Integral color is the procedure where the entire volume of concrete is dyed the base color. The entire volume of concrete is colored by adding the color hardener to the concrete truck, and allowing all the concrete in the truck to be dyed. Cast-on color is the procedure where the surface of the concrete is dyed the base color. The surface of the concrete is colored by spreading the color hardener onto the surface of the wet concrete and floating the powder into the top layer of the wet concrete.