Red Iron Oxide
- Red Iron Oxide (Fe2O3) is the normal state of iron oxide. It is the most oxidized form, and when it is reduced, it is reduced to black iron oxide. This chemical is 81% Fe2 O3, and is bright red in its raw, powdered form. As a glaze component, it can create varied effects depending on the conditions. In general the following occurs with iron oxide:
- Oxidation firings produce red iron oxide reduction firings produce black iron oxide
- The amount of iron oxide present in a glaze will affect the colors as well. Iron oxides can be used in slips and washes and can also be applied directly to the clay body surface, a technique often employed to create a textured appearance. Suggested concentrations of iron are as follows:
- 0.5- 8% in slips up to 15% in glazes
- Because the ranges of concentrations are so broad, we recommend that you consult one of the many useful glaze recipe books that are available for reference.
- In its powdered form, red iron oxide can cause skin, eye irritation and sensitization, and is very harmful if inhaled. Please use protective coverings when handling this chemical.