Yasutomo Mineral Paper is crafted from calcium carbonate gathered from rocks instead of tree pulp. Mineral Paper provides an environmentally friendly alternative to traditional wood based paper. Mineral Paper is acid-free and composed of 80% calcium carbonate and bonded together with a small amount of HDPE (plastic). It offers unique qualities such as tear and water resistance and avoids bleed through even when soaked. This 100 lb. (150 gsm) features an absorbency suited for almost any media, wet or dry, and is even compatible for use with ink jet printers. The bright white color and vellum surface of the paper allows for crisp lines and saturated colors. Sheets measure 9 in. x 12 in. and are sold as a pack of 2 for a total of 40 sheets (20 sheets each).