Notes
Old number: 183
Related Information
Each Mason stain has its own personality for coloring the body
This picture has its own page with more detail, click here to see it.
These Mason stains make the porcelain more refractory, but some more so (e.g. 6385, 6226). Some do not develop the intended color (e.g. 6006 pink, it is a glaze stain only). Some need a higher concentration (e.g. 6121, 6385). Some need a lower concentration (e.g. 6134). Some do not impart a homogeneous color (e.g. 6385). The data sheets from the stain manufacturer normally make it clear which of their stains are suitable in bodies. But it is up to you to test concentrations needed to get the desired color and what adjustments to the porcelain are needed to compensate its degree of vitrification in response to the effects of the stain.
Same glaze, same stain percentages
Yet two stains give completely different results
This picture has its own page with more detail, click here to see it.
- Left: A cone 6 matte glaze (G2934 with no colorant).
- Middle: 5% Mason 6006 chrome-tin red stain added.
- Right: 5% Mason 6021 encapsulated red stain added.
Why does the red color not develop in the center glaze? This host recipe does not have the needed chemistry to develop the #6006 chrome-tin color (Mason Colors provide glaze unity formula guidelines: 6.7–8.4% CaO and avoiding MgO). This glaze recipe calculates to 9.8% CaO and 5% MgO. The MgO is the likely reason the red fails to develop. Yet this glaze produces excellent color with #6021 encapsulated stain (right). It isn't automatic that a strong red is achieved at just 5% encapsulated stain. The color is embedded in zircon crystals and aggressively melting KNaO, which this base recipe has very little of, attacks them and reduces color intensity.
Links
