This color contains the following pigments:
Fe2O2 or Fe2O3 • H2O
Mars Orange is a bright, extremely light red and appears almost pinkish in contrast with darker colors. It has incredible tinting strength and opacity. The synthetic form of Mars Orange is made from iron oxides and is cleaner, brighter, and denser than its ochre-based counterparts.
Mars Orange has excellent permanence and lightfastness.
Mars Orange has no significant hazards.
The word Mars refers to the Roman god of iron and war. Mars Orange has been manufactured as a pigment since the 17th century.
hydrated iron oxide
α-FeO3+(OH) or Fe2O3 × MnO2
Raw Umber is a cool, transparent brown ranging from yellowish brown to greenish brown. It has surprisingly good tinting strength, a high level of opacity, mixes well with greens, and is quick drying in oil form. It has excellent color properties and can create a variety of subtle, clear tints when mixed with white. It grays when mixed with blue and white. Raw Umber can tend towards chalkiness in dark mixes in oil form.
Raw Umber has excellent permanence.
Raw 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.