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Umber

Umber
 
About these coordinates     Color coordinates
Hex triplet #635147
sRGBB  (rgb) (99, 81, 71)
CMYKH   (c, m, y, k) (0, 18, 28, 61)
HSV       (h, s, v) (21°, 28%, 39%)
Source ISCC NBS
B: Normalized to [0–255] (byte)
H: Normalized to [0–100] (hundred)
Raw Umber
 
About these coordinates     Color coordinates
Hex triplet #826644
sRGBB  (rgb) (130, 102, 68)
CMYKH   (c, m, y, k) (0, 22, 48, 49)
HSV       (h, s, v) (33°, 48%, 51%)
Source ISCC NBS
B: Normalized to [0–255] (byte)
H: Normalized to [0–100] (hundred)
Burnt umber
 
About these coordinates     Color coordinates
Hex triplet #8A3324
sRGBB  (rgb) (138, 51, 36)
CMYKH   (c, m, y, k) (0, 63, 74, 46)
HSV       (h, s, v) (9°, 74%, 54%)
Source Xona.com Color List
B: Normalized to [0–255] (byte)
H: Normalized to [0–100] (hundred)

Umber is a natural 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 d'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. Commercial colors vary depending upon the manufacturer or the color list. Not all umber pigments contain natural earths; some contain synthetic iron and manganese oxide, indicated on the label. Pigments containing the natural umber earths indicate them on the label as PBr7 (Pigment brown 7), following the Colour Index International system.

The color shown in the box at right is one of the many commercial varieties of umber, from the ISCC-NBS color list: ISCC-NBS Dictionary of Color Names (1955)—Color Sample of Umber (color sample #61).

Umber was one of the first pigments used by humans; it is found along with carbon black, red and yellow ocher in cave paintings from the neolithic period.

Dark brown pigments were rarely used in Medieval art; artists of that period preferred bright, distinct colors such as red, blue and green, rather than colorless colors. The umbers were not widely used in Europe before the end of the fifteenth century; The Renaissance painter and writer Giorgio Vasari (1511–1574) described them as being rather new in his time.

The great age of umber was the baroque period, where it often provided the dark shades in the chiaroscuro (light-dark) style of painting. It was an important part of the palette of Caravaggio (1571–1610) and Rembrandt (1606–1669). Rembrandt used it as an important element of his rich and complex browns, and he also took advantage of its other qualities; it dried more quickly than other browns, and therefore he often used it as a ground so he could work more quickly, or mixed it with other pigments to speed up the drying process. The Dutch artist Johannes Vermeer used umber to create shadows on whitewashed walls that were warmer and more harmonious than those created with black pigment.


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Wikipedia

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