Velvet Underglaze with Various Firing Temperatures

by Chanicha T

One of the most frequently asked questions about AMACO Velvet Underglaze is what is the maximum firing temperature?

The answer is that Velvet underglazes are designed to be used in a wide temperature range, from Cone 06 to Cone 10 (approximately 999–1305°C), but the appearance of the color will change depending on the firing temperature.

 

Low Fire (Cone 06–04)

Low-firing temperatures are the range where Velvet Underglaze provides the most vibrant and complete range of colors. All shades can be used effectively. It is suitable for decorative work, ceramic painting, and projects that require bright, crisp colors.

 

Mid Fire (Cone 5–6)

In the mid-fire range, Velvet still provides beautiful colors and increased durability, but some shades may change, such as becoming darker, paler, or starting to melt into a semi-matte, semi-gloss (Satin) finish. If it is a food-safe vessel, it should be clear-glazed for safe use. Choosing colors suitable for the temperature will help the fired colors remain vibrant and as close to the desired result as possible.

For firing at Cone 5–10, it is recommended to choose certain shades that are suitable for high temperatures, such as:

  • Use Cactus instead of Light Green because Light Green often darkens when fired at high temperatures.
  • Use Coral instead of Rose because Rose may fade or lose its vibrancy in Mid Fire and High Fire.
  • Use Medium Blue instead of Electric Blue because Electric Blue often changes to a very dark blue when fired.
  • Use Amethyst instead of Purple because Purple tends to shift towards blue tones when fired at high temperatures.
  • Use Red Brown instead of Teddy Bear Brown because Teddy Bear Brown is more likely to melt and run when fired at high temperatures.

 

High Fire (Cone 9–10)

Velvet Underglaze can be fired up to Cone 10, which is suitable for stoneware and porcelain, as well as Reduction and Salt Firing.

When fired at very high temperatures, some shades may fade or intensify significantly, so it is advisable to conduct a test firing before actual production, especially if color consistency is desired. On the other hand, some color groups yield excellent results at high temperatures, including black, red, and certain shades of blue. Even when fired in a Reduction kiln, they still maintain beautiful colors.

AMACO Velvet Underglaze can be fired from Cone 06 to Cone 10 (approximately 999–1,305°C), thus covering low, mid, and high-fire ceramic work. However, since each shade responds differently to heat, it is important to choose shades suitable for the intended temperature range and to conduct test firings before actual use to achieve the most desired results.

 

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