Black pumice stone
Natural black volcanic pumice stones drilled through and threaded with cotton cord. Used wet to remove calluses and hardened dry skin. Pumice is formed by the sudden depressurisation of super-heated lava, usually during the more violent phases of volcanic eruptions, rapidly cooling as trapped gasses inside expand the lava petrifies into a remarkably light and sponge like form. Stones of very approximately 5cm diameter.