Quick view U.S.P Menthol Crystals | Lotions, Balms, Salves, DIY Project U.S.P Menthol crystals Our U.S.P Menthol crystals have a minimum 99.5% L- menthol content. They are 100% pure and natural. The essential oil from mint (mentha arvensis) is used to form these potent menthol crystals. The manufacturers we... Was: Limited Time: $48.50 - $89.75 Choose Options Compare