Spectrumë_offers a full palette of rich, vibrant colors that are opaque with 3 coats, semi-opaque with 2 coats and semi-transparent with 1 coat.
Spectrum underglaze colors are lead-free, A/P non-toxic and dinnerware safe when covered with a dinnerware safe clear glaze. They are compatible for use under most clear glazes.
Spectrum underglazes use a frit base rather than a slip (clay) base. The advantages to the user are that our underglazes can be applied on greenware or bisque and they can be used with or without a clear glaze covering. When used without a clear glaze cover they have a matte velvet like surface. However, when used without a clear glaze cover they are not considered dinnerware safe because the rough surface can be difficult to clean and can encourage bacteria growth.
The color chart shows the unglazed color in the lower right half of the tile and the color when covered by a clear gloss glaze in the upper left half of the tile. The color chart samples were fired at cone 05. Our underglazes generally have good temperature stability up to cone 6 and for many colors to cone 10. When fired hotter than cone 04 you may get small color variations from those shown on our charts, so please test them for your application.
Underglazes all come in 4 oz jars.
* Some of Spectrum underglaze colors will start to look glossy without any clear glaze cover at cone 5.
These underglazes can be intermixed to create your own colors. However, we recommend not mixing 561, 562, 563, 567, 568, 569 with any of the other colors.
These colors are based on cadmium encapsulated stains that do not mix well with other ceramic stain colors.