B on B: Gingko lattice

This is how Black-on-Black finish is made: by terry hagiwara

1. Apply terra sig. on the bone-dry surface and burnish.
   • i use ball-clay slip for terra sig.
   • burnish when the terra sig. start losing its wet appearance before it gets dry
   • this means, apply terra sig. and burnish patchwise, if necessary, over a large surface and burnish the entire surface
   • important: the piece must be thoroughly dry. if not, moisture of the clay permeate into burnished terra sig. later and disasrray the clay particle alignment (by swelling), thus causing the surface to lose its sheen. retaining surface sheen is crucial to obtain the "wet" (shiny reflective) black surface eventually.
   
   
2. Bisque fire to cone O9 or O10.
   • this is important: if fired to O6 (as in regular bisque-firing), the surface lose its sheen.
   
   
3. Apply/brush very thin clay-slip for design on bisqued surface.
   • i use the same clay used for the piece.
   • i use a 6B or softer pencil for contouring design, if necessary.
   • i also use sign-pen (water-proof). water-proof helps to keep a crisp boundary between "dull" and "wet" blacks. it prevents waterly slip from crossing the boundary.
   
   
4. Fire and smoke.
   • if you are using raku kiln, fire to low temperature, just high enough to burn off 6B pencil (or marker) lines.
   • smoking doesn't require red-hot firing as needed for regular raku glazes. just hot enough to ignite paper or saw dust in the smoking chamber (can) to generate smoke.
   • important: if fired to O7-O6 range, the surface lose its sheen and when smoked, the surface is no longer "wet" black, although it is still different from "dull" black on the slip-painted surface.

• the difference of the surface, the burnished vs. the clay-slipped, creates two different shades of black. instead of slip painting, i can also remove terra-sig from the surface (by scraping off with sharp knife), thus to create two different surface textures. (of cource, before bisque-firing.)
• or, in yet another approach, bisque-fire first and apply terra sig. and burnish, then scrape off, instead of slip-painting. however, in this method, some thickly applied terra-sig sometimes peels off after smoking leaving white scars.
• but, slip painting is much easier and quicker.