Paper clay is any clay body to which processed cellulose fiber has been added.
A paper clay turtle
Clay is a type of fine-grained natural soil material containing clay minerals. Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as
Paper clay
…Paper clay (sometimes referred to as fiberclay) is any clay body to which processed cellulose fiber (paper being the most common) has been added. Earthenware, terra cotta, stoneware, porcelain and bone china…
Boulder clay cliff south of Withernsea, England
A 23,500 times magnified electron micrograph of smectite clay
Italian and African-American clay miners in mine shaft, 1910
Clay layers in a construction site in Auckland, New Zealand. Dry clay is normally much more stable than sand in excavations.