V-375 Maroon UnderglazeMaroon Velvet Underglaze is a deep burgundy color that is soft and rich at cone 05, deepens at cone 5, and begins to burn out at cone 10. A clear glaze deepens the color of the underglaze significantly at cone 05 and intensifies its rich oxblood shade at cone 5. Due to variations in raw materials used during manufacturing, we recommend firing glazed test tiles before using each new batch number of glaze.