Birch is one of the Texas Two Step Overcoats, and can be layered with Licorice, Coffee Bean, or Brick Red to produce an oilspot effect.  It can also be used on its own for a slightly mottled, neutral color.

The Texas Two-Step Oilspots are a specialized series that use pairs of glazes to create unique effects. Anywhere that one of the five overcoats is laid on top of Licorice, Coffee Bean or Brick Red, a stunning spotted pattern will appear during firing. Thicker applications lead to bigger spots. Try using wax resist after the first layer to create negative space designs.