Rock Salt concrete is considered a step above smooth or broom-finished concrete, a salt finish leaves a speckled pattern of shallow indentations on the concrete surface, similar to the appearance of slightly pitted, weathered rock. As the name implies, a salt finish is traditionally achieved with the same coarse rock salt sold for use in water softeners or as a de-icer in winter. Salt finishes are attractive alone, but are particularly stunning when used in combination with colored concrete and other decorative finishes.