Iron Oxide brown
|
|
Iron Oxide Brown
|
|
|
Color Index
|
Pigment Brown 6, 7
|
|
|
Formula
|
Fe2O3
|
Structure
The natural form of Brown Iron Oxide is called burnt sienna or burnt umber. Pigments
are made from naturally occurring ores that are then heated. The various shades
obtained are dependent on the impurities, especially the manganese oxide content.
Brown Iron Oxide can also be synthesized.
Properties
Natural brown iron oxide has a low tinting strength but is not opaque.
The synthetic grades impart a rich brown color and give excellent fastness properties.
Uses
Synthetic brown iron oxides are not used in paint formulations, as similar shades
can be obtained using mixtures of cheaper pigments.
Burnt sienna and burnt umber have become well known due to their use for artists'
colors. But they can be used in commercial paints.
