A nice brown fine clay powder to convert to slip in plaster mold casting. To deflocculate powder, add 1 tablespoon sodium silicate and half tablespoon soda ash to 2 litre tap water. Stir water and sprinkle in powder to mix well. Allow overnight to mature clay. Fine tune slip viscosity if necessary by adding more powder or Rheotan L deflocculant without adding more water. Too much water in slip will over saturate mold with reduce number of cast per mold. Fill plaster mold full with slip. Top up till wall thickness is formed as water is being absorbed into the plaster mold. Pour out excess slip once desired wall thickness is achieved. Demold cast let dry till leatherhard dry before firing to cone 03 or 1060 deg C . The brown clay fires to white earthernware bisque. Clay shrinkage is 10 – 12 %.
The chocolate brown clay is a plastic clay as the natural organic carbonaceous lignite contributes much to clay plasticity and color. As a soluble organic color it will not affect plaster performance. In fact its rich chocolate color do assist in clay sculpting as it high light any surface unevenness.
