Almost weightless, Pumice is rough textural volcanic glass. Applied smoothly, it produces a consistently rough, flat surface. Capable of creating unusual textures on large canvasses due to its light weight, Pumice is also suitable for mixed media, collage and collograph plates. Up to equal parts pumice can be added to either MM2 Impasto Medium, MM4 Gel Medium, MM6 Polymer Matt Varnish (water-based), MM7 Gloss Varnish and Gloss Medium, MM28 Polymer Satin Varnish (water-based) or MM30 Matt Gel Medium.