Natural Pumice Stone for Feet Stone Foot Scrubber Pummice Stone Feet Stone It's best to soak your feet in warm water for a while Soak your feet for at least 5 mins but, ideally, for 15 mins to get your skin extra soft. Use a towel to dry your feet gently Rough side to scrub It also fit for rough, hard, dry, thick skin. Works to clean, exfoliate and smooth calluses.