Body color properties are attached to material records for materials that have an influence on this phenomenon. Name the color and add notes regarding any circumstances that affect the development and maintenance of the color.
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- When added to terra cotta bodies in amounts around 5% manganese dioxide will produce dark gray to black firing bodies.
- CoFeMn, CoFeMnNiCr stains are suitable for most types of bodies for firing at temperatures to 1300C+.
- CrSi stains are particularly suitable for the staining of vitreous floor tile bodies. Suitable for all other types of bodies under all firing conditions, but use is limited owing to the tendency of the chrome contents of the colors to flash.
- Admirably suited to staining all types of bodies because of freedom from tendency to strike or flash.
In reducing conditions, tin-based greens should not be used.
- Engobe or Body Stain: Suitable for all types of bodies and slips.
No tendency to strike or flash.
Extremely stable under reducing conditions
- In low fire the presence of iron produces red terra cotta colors that progress to brown with maturity. High temperature red bodies depend on stopping firing well short of vitrification. In higher temperature vitreous bodies fired in reduction iron is converted to actively melting black iron oxide that teams up with feldspathic melts that can dissolve benificial mullite and quartz crystals. As iron - rich liquids cool into glass, the glass has a brittle character.
- Rutile sand (granular) can be used to add speck to bodies.
Oxides - CoOIn magnesia glazes a color range is from violet to lilac is possible.
- Rutile can be added to low fire bodies to make them burn golden yellow.