This is the Terra sigilatta that I use on my work, and color with a range of Mason stains for color.  This comes in pints, and fires to a nice soft white. Primarily used at a low earthenware temperature range, terra sig can be used for saggar firing, low temp salt and soda, as well as high temp wood and soda kilns.When burnished with plastic stretched over your finger a wonderful sheen is given to the surface.  Specific gravity of 1.13 when packaged.  Enjoy!!