This color contains the following pigments:
Fe2O2 or Fe2O3 • H2O
Mars Orange is a bright, extremely light red and appears almost pinkish when contrasted 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 good 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.
Fe2O3 • H2O
Yellow Ochre provides artists with earthtones from cream to brown. It has good hiding power, produces a quick drying paint, and can be safely mixed with other pigments. Its transparency varies widely from opaque shades to more transparent ones, which are valued for their use as glazes. If gypsum is present, Yellow Ochre is not suitable for frescoing. (See Brown Ochre, PY43.) PY42 is made from synthetic iron oxides. PY43 is made from natural iron oxide.
Yellow Ochre has excellent permanence because ochres are some of the most permanent pigments available.
Yellow Ochre is non-toxic unless it contains manganese.
Ochre comes from the Greek word ochros, meaning pale yellow. It was one of the first pigments to be used by human beings, and evidence of its use has been found at 300,000 year old sites in France and the former Czechoslovakia.