Mineral Paper is similar to traditional wood pulp-based paper but is made with calcium carbonate from rocks rather than tree pulp and is considered to be an environmentally friendly alternative. This water-resistant paper has a smooth finish, yet enough tooth and absorption for use with a variety of mediums including inks, paints, pencil, pastel, pen and marker. It's strong enough to be embossed and is tear resistant for many uses including delicate die cuts. It is light-weight, yet won't buckle even with the wettest mediums. Each pad contains 20 sheets of bright white, vellum surface, acid-free 100lb. mineral paper.