Underglaze colours may be applied onto greenware or bisqueware using a suitable water based media (see 47051 Underglaze Media). Mixing of colour and media must be very thorough and is best achieved by working the colour into the media using a palette knife in a rubbing or lapping action. If sufficient flux is added, colours and stains can be made self-glazing and matt/satin colours developed. Powdered underglazes can also be used as glaze or body stains.
All powdered underglazes in this section are colour-stable to 1300C with the exception of 4530 Flesh Tint, 4531 Crimson, 4532 Purple Damson and 4550 Brick Red which are colour-stable to 1140C. Also, these four Chrome-Tin colours, plus 4542 Victoria Green, are not generally recommended to be used as slip or body stains due to unreliable colour response but should perform satisfactorily in a glaze.
Powdered glazes, once mixed with water according to the recommended guidance, are suitable for dipping, pouring or spraying onto the piece. They are not suitable for brushing-on without addition of a glaze binder such as Pehatine. If brush-application is intended, we would recommend you select one of our ready-mixed brush-on glazes instead.
Transparent glazes must be applied thinly and fired/cooled on a fast schedule to avoid ‘milkiness’ and/or crazing in the fired result.
Artistic/special effect glazes usually require a generous application to achieve the desired effect. Please note the individual product descriptions for product-specific guidance. Some special effect glazes can melt/flow considerably during firing so please take all necessary precautions, especially with regard to protecting your kiln furniture (stilting, batt wash etc.).