This color contains the following pigments:
Cadmium Yellow is brilliant, dense, and opaque, with good tinting strength and very high hiding power. It is the artist’s principal bright yellow and is available in light, medium, and dark shades. The deeper shades appear deep orange and have the greatest tinting strength. It is slow-drying in oil form and is used in both oil and watercolor form. It cannot be mixed with copper-based pigments. A clean Cadmium Orange is created when Cadmium Yellow is mixed with Cadmium Red. Hues vary by brand. Cadmium pigments have been partially replaced by azo pigments, which are similar in lightfastness to the cadmium colors, cheaper, and non-toxic. Cadmium Yellow is usually available in a pure grade, or in a cadmium-barium mix. This mix has the same permanence with a lower tinting strength.
Cadmium Yellow is lightfast and permanent in most forms, but like most cadmium colors, it will fade in fresco or mural painting. The deeper shades are the most permanent. The pale varieties have been known to fade with exposure to sunlight.
Cadmium Yellow is a known human carcinogen. It can be hazardous if chronically inhaled or ingested.
Cadmiums get their names from the Latin word cadmia meaning zinc ore calamine, and the Greek word kadmeia, meaning Cadmean earth, first found near Thebes, the city founded by the Phoenician prince Cadmus. Metallic cadmium was discovered in 1817 by Friedrich Strohmeyer. Oil colors were first made from Cadmium Yellow pigments in 1819, replacing toxic Chrome (lead) Yellows. However, their production was delayed until 1840 due to the scarcity of cadmium metals. Landscape painters, such as Claude Monet, preferred Cadmium Yellow to the less expensive Chrome Yellow because of its higher chroma and greater purity of color.
Zinc White is the coolest white, and it has a cold, clean masstone and a slightly bluish tint. It has less hiding power and is more transparent than other whites. It dries slowly and is good for painting wet into wet and for glazing and scumbling. Zinc White is neither as opaque nor as heavy as Lead White, its covering power is not as good, and it takes much longer to dry. However, it does not blacken when exposed to sulfur in the air as Lead White does. It is very valuable for making tints with other colors. Unmixed Zinc White dries to a brittle and dry paint film that may crack over the years, so it is not good for frescoing. It is more transparent in acrylic form than Titanium White and is the most commonly used white with gouache. Chinese White is a version of Zinc White appropriate for opaque watercolor techniques.
Zinc White has great permanence and lightfastness.
Zinc White is moderately toxic if ingested and slightly toxic if inhaled.
Though historians are divided on who first isolated the element zinc, they agree that it was first suggested as a white pigment in 1782. Zinc White was accepted as a watercolor in 1834 and was called Chinese White due to the popularity of oriental porcelain in Europe at the time. Ten years later, a suitable oil form was produced. By the early 20th century, it had improved to the point where it was an acceptable alternative to Flake White.