Lava Pumice Stones Volcanic Rocks Black Red Surface Interior Color Cut Form Decoration Origin Type Stairs Size Tiles Grey Place. ... Minerals Machinery Co., Ltd. 12 YRS. Contact Supplier. 1/6. ... Grinding Foot Stone Exfoliating Scrub Natural Volcanic Rock Remove Calluses. / .
Nov 18, 2011 · Clastic sedimentary rocks: These sedimentary rocks form from the breakdown material of other rocks. When a rock is exposed to the elements, it will begin to erode. ... This is the result of volcanic activity, approximately 180 million years ago, that caused molten rock to be injected between layers of sandstone.