This color contains the following pigments:
iron(III)-oxide, partly hydrated
Brown Ochre provides artists with earthtones from cream to brown and is a dull, dark variety of Yellow Ochre. Its transparency varies widely from opaque shades to more transparent ones, which are valued for their use as glazes. It has good hiding power, produces a quick drying paint, and can be safely mixed with other pigments. The highest quality Brown Ochre comes from Cyprus, where it is yellow in its raw form and is roasted to get the deeper brown-red varieties that result when water is removed. (See Yellow Ochre, PY42/43.)
Brown Ochre has excellent permanence.
Brown Ochre is non-toxic.
Ochre comes from the Greek word ochros, meaning pale yellow. It has been used since prehistoric times, and evidence of its use has been found in some of the earliest known cave paintings in Lascaux, France. It has also been called Goethite, after the German philosopher and mineralogist Johann Wolfgang von Goethe (1749-1832).
Titanium White is the most brilliant of the white pigments. It is considered an all purpose oil color useful in all techniques and the best all around white. Its masstone is neither warm nor cool, placing it somewhere between Lead White and Zinc White. It is less prone to cracking and yellowing than Lead White, but it still yellows easily. Titanium White dries slowly in oil form, more slowly than Lead White but more quickly than Zinc White. It is opaque in oil and acrylic forms and semi-opaque in watercolor form. This pigment has good chemical stability, and its tinting strength is superior to both Lead White and Zinc White.
Titanium White has excellent permanence and lightfastness.
Titanium dioxide is highly stable and is regarded as completely non-toxic. Animal studies give no indiciation that it is absorbed biologically, even after long periods of exposure. The primary safety concern is with inhalation of fine pigment dust particl
Titanium is the ninth most abundant element in the Earth's crust, however mineral deposits that are economical to mine are less common. Titanium dioxide was first discovered in 1821, although it could not be mass produced until 1919. Widespread use of the pigment began in the 1940s. Since that time, it has become the most commonly used white pigment. The name comes from the Latin word Titan, the name for the elder brother of Kronos and ancestor of the Titans, and from the Greek word tito, meaning day or sun.