Ampersand Art Claybord, Uncradled, 1/8" Profile, 5" x 5" 4/Pkg.. Museum Series Claybord is made using 1/8" hardboard and features a kaolin clay ground formula that is sanded to an ultra-smooth, highly absorbent finish. Your paint colors will remain true and brilliant, and the smooth surface can be worked into. Simply apply a thin layer of paint or ink, remove it, reapply it, even scratch through it to add contrast, texture and fine details. Claybord is a versatile surface that can be used with inks, egg tempera, acrylics, collage, pencil, pen, airbrush, photo-transfers, casein, watercolor, gouache, mixed-media, and to mount papers, prints and fabrics.