Buy Mr. Pumice Manicure Pedicure Tools - Mr. Pumice Pumi Bar Ultimate (Coarse/Green - Medium/Lavender) 1 Pumice Bar. How-to-Use: Apply a little soap and warm water on callus. Use LAVENDER side to remove callus on feet. Gently rub GREEN side on feet and smooth skin to a soft, silky finish. Rinse PUMICE BAR under hot water after each use.