Umber is a natural occurring ore brown or reddish-brown earth pigment that contains iron oxide and manganese oxide. It is darker than the other similar earth pigments, ochre and sienna.
In its natural form, it is called raw umber.
When heated (calcinated), the color becomes more intense, and the color is known as burnt umber.
The name comes from terra di ombra, or earth of Umbria, the Italian name of the pigment. Umbria is a mountainous region in central Italy where the pigment was originally extracted. The word also may be related to the Latin word Umbra.
Umber is not one precise color, but a range of different colors, from medium to dark, from yellowish to reddish to grayish. The color of the natural earth depends upon the amount of iron oxide and manganese in the clay. Umber earth pigments contain between five and twenty percent manganese oxide, which accounts for their being a darker color than yellow ochre or sienna.
It comes in two varieties:
- Raw earth umber (Raw Sienna earth): the earth just mined and ground into a pigment.
- Burnt umber (Burnt Sienna earth): the raw earth umber pigment is also calcinated in order to get darker shades.
Umbers:
How it is made: Burnt umber is a combination of iron oxide, oxide of manganese and clay, made by burning raw umber to drive off the liquid content.
Chemical Properties: Dark brown umbers contain 45% to 70% iron oxide and 5% to 20% manganese dioxide.