A light but unyielding blue
Coyote Underglazes are the only commercially available underglazes specially designed to be fired at cone 5-6. The colors can be mixed, and stay true and stable up to cone 10 in oxidation. They are always bold and striking, and are suited to functional ware when covered in Coyote Gloss Clear and fired to cone 6. They can be used on either greenware or bisque.
|Every kiln and firing is different. It is best to use witness cones in every firing.
Coyote glazes are designed to be fired between witness cone 5 and witness cone 6.
Cone readings are a combintation of time and temperature, and do not correspond directly to any specific temp in degrees. Most digitally controlled kilns have a pre-programmed cone fire setting that will allow you to reach the proper temperature with minimal fussing (we use a cone 5, fast, with 30 minute hold.) For manual (sitter) kilns we recommend using a 6 cone.
Thermocouples and other electronic measuring devices are prone to error and degrade over time. The only way to be certain that your kiln is firing to the right temperature is to use witness cones every time you fire your kiln.