This shade can be used for both kiln-forming and stained glass. An opaque and glossy shade, this classic Black melts beautifully for a uniform surface. Prone to devitrification if the surface is dirty when it's fired.
Consistent colour. Although termed an opal due to its almost total lack of light transmission, this is (in terms of its composition) actually a transparent glass.
Low viscosity. Will flow sooner and more than other glasses. In very thin sections the colour may vary from reddish/grey to