This color contains the following pigments:
iron oxides with manganese silicates or dioxide
Fe2O3,MnO2 or Fe2O3 + MnO2 + nH2O + Si + Al2O3
Burnt Umber is a more intense reddish brown pigment that results from heating the clay pigment Raw Umber. It has medium to excellent tinting strength and high opacity, and it is quick drying in oil form. Burnt Umber is somewhat more transparent than Raw Umber. It has excellent color properties and can create a variety of subtle, clear tints when mixed with white. It can tend towards chalkiness in dark mixes in oil form, but overall it mixes well with other colors. To create a black color in oil form, mix Burnt Umber with Phthalo Blue or Ultramarine. To achieve a similar color in watercolor form, mix it with Ultramarine or Payne's Gray.
Burnt Umber has good permanence.
Burnt Umber itself is considered non-toxic. If contaminated by manganese compounds, it may be highly toxic if inhaled and moderately toxic if ingested.
This pigment gets its name from the Latin word umbra, meaning shadow or shade. Its full name is listed as terra di ombra, meaning earth of shadow/shade, due to its original extraction from the area of Umbria, Italy. It has been used as a pigment since prehistoric times. Currently, the finest umber comes from Cyprus.
beta copper phthalocyanine
Phthalo Blue PB15:3 is a structural variant of Phthalo Blue PB15 that produces more greenish tones.
Phthalo Blues are completely lightfast and stable and are permanent for all paint uses. They are currently used in inks, coatings, and many plastics due to their stability and are considered a standard pigment in printing ink and the packaging industry.
Phthalo Blues have no significant hazards, although those made before 1982 contained some PCBs (polychlorinated biphenyls).
Developed by chemists using the trade name Monastral Blue, the organic blue dyestuff now known as Phthalo Blue was presented as a pigment in November 1935 in London. Its discovery was accidental. The dark color was observed in a kettle where a dye was being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted a cyan to replace Prussian Blue.