Matt Underlay is a yellow powder that can be mixed with your regular Mixing Medium. Carefully paint the design you want matted on your glazed piece. Clean all edges so they are crisp and sharp. Fire to Cone .014 – .016, 1596 – 1517F. The Matt Underlay design will be a soft, matt yellow in color after firing. Paint Liquid Bright Gold over the entire area. The background glaze will be bright and the design will be a soft etched appearance.